Authorities believe the body of a third missing construction worker has been located in the rubble of a collapsed parking garage on the Doral campus of Miami Dade College, according to Miami Dade Fire Rescue, though rescuers are still working to reach the area.

Four floors of the nearly-completed, $24 million 5-story structure collapsed in pancake fashion around 11:40 a.m. Wednesday. No students were inside the garage when it fell, but instead it was full of dozens of construction employees and subcontractors.

One man was previously confirmed dead, a second body was found late Wednesday afternoon, and a Miami-Dade Rescue official told HuffPost Wednesday evening that K-9 units have indicated the location of apparent remains believed to be third and last person unaccounted for.

"It fell to the ground like a house of cards," Victoria Buczynski, who was working across the street, told the Associated Press. "The construction workers started running out, screaming. It was loud. Our entire building shook."

Rescue workers who spent hours trying to extricate another worker from the collapse finally decided to amputate his legs above the knee, according to the Miami Herald, who reported he was rushed to a nearby hospital in extremely critical condition.

MDFR spokesperson Griselle Marino said the man had been pinned from the waist down inside a truck cab crushed in the collapse, and a trauma surgeon was assisting MDFR's entire tactical response team, a highly-trained veteran group who saw action after collapses during the 2010 Haiti earthquake and September 11, with his rescue.

"He needs so much medical attention, his legs are crushed," Marino said earlier of the man, who was given an IV while rescuers tried to free him without losing his legs. "It's a decision you or I wouldn't want to make."

Another man was previously extricated alive from the collapse (see footage below) and is currently in critical condition at a local hospital.

A total of nine workers have been transported to hospitals and trauma centers and two men were treated on scene. More than 90 fire crews and K-9 units responded to assist in the massive search and rescue effort. (Story continues below.)

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  • Robert Budhoo

    This undated family photo provided by the Budhoo family, shows Robert Budhoo, the missing construction worker believed to be trapped in the collapse parking garage at the Miami Dade west campus in Doral, Fla. (AP Photo/Budhoo Family)

  • Unidentified family members of Robert Budhoo, who is missing after a parking garage collapsed at the Miami Dade College West campus in Doral, Fla., wait for results of the search through the rubble Thursday, Oct. 11, 2012, in Doral. (AP Photo/J Pat Carter)

  • An unidentified family member talks about Robert Budhoo, who is missing after a parking garage collapsed at the Miami Dade College West campus in Doral, Fla. Thursday, Oct. 11, 2012. The family is still waiting for results from the search through the rubble. (AP Photo/J Pat Carter)

  • Steve Budhoo

    Steve Budhoo, the brother of Robert Budhoo, who is believed to be still trapped in the collapsed parking garage at the Miami Dade College West campus in Doral, Fla., talks about his brother Thursday, Oct. 11, 2012, in Doral. (AP Photo/J Pat Carter)

  • Bill Byrne, president and CEO of Ajax construction company, gives a statement to the press Thursday Oct. 11, 2012, in front of the collapsed garage his company was contracted to build by Miami Dade College in Miami. Part of the building fell Wednesday and killed at least two construction workers and sent at least 10 workers to local hospitals and one man is missing. Byrne said," we don't know what happened yet and our concerns now are with the families of those who died or are missing." (AP Photo/The Miami Herald, Tim Chapman) MAGS OUT

  • College Garage Collapse

  • In this photo provided by Miami-Dade Fire Rescue, emergency workers remove an injured man from the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)

  • A Fire Rescue team member and her dog search for victims trapped in the collapsed parking garage at the Miami Dade College West campus in Doral, Fla. Tuesday, Oct. 10, 2012. One worker was killed and two others were trapped in the rubble. (AP Photo/J Pat Carter)

  • A Fire Rescue team member and rescue dog search for victims trapped in the collapsed parking garage at Miami-Dade College West campus in Doral, Fla. Tuesday, Oct. 10, 2012. One worker was killed and two others were trapped in the rubble after a section of the under-construction parking garage collapsed. (AP Photo/J Pat Carter)

  • Fire Rescue officials work to remove a victim from the collapsed parking garage at the Miami Dade College West campus in Doral, Fla. Tuesday, Oct. 10, 2012 . A section of a parking garage under construction at a community college collapsed killing one worker and trapping two others in the rubble, officials said. At least 10 other workers were hurt when the roof of the five-story concrete garage fell, creating a pancake-style collapse on the campus of Miami-Dade College, officials said. (AP Photo/J Pat Carter)

  • Miami-Dade Fire Rescue workers work the scene of a parking garage collapse at Miami-Dade College in Miami on Wednesday, Oct. 10, 2012. A section of the under-construction parking garage collapsed, killing one worker and trapping two others in the rubble, officials said. At least 10 other workers were hurt. (AP Photo/The Miami Herald, Hector Gabino) MAGS OUT

  • A dog walks through the rubble, lower left, with rescue workers at a five-story parking garage after it collapsed at Miami-Dade College, Wednesday, Oct. 10, 2012 in Miami, killing one worker and trapping two others in the rubble, officials said. Several other workers were hurt, including one rescued from the debris. (AP Photo/Lynne Sladky)

  • In this photo provided by Miami-Dade Fire Rescue, emergency workers bring an injured man to an ambulance after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)

  • A rescue worker walks through the rubble at a five-story parking garage after it collapsed at Miami-Dade College, Wednesday, Oct. 10, 2012 in Miami, killing one worker and trapping two others in the rubble, officials said. Several other workers were hurt, including one rescued from the debris. (AP Photo/Lynne Sladky)

  • A five-story parking garage is shown after it collapsed at Miami-Dade College, Wednesday, Oct. 10, 2012 in Miami, killing one worker and trapping two others in the rubble, officials said. Several other workers were hurt, including one rescued from the debris. (AP Photo/Lynne Sladky)

  • In a photo provided by Miami-Dade Fire Rescue, firefighters look over the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)

  • In a photo provided by Miami-Dade Fire Rescue, firefighters search the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)

  • A rescue worker watches his search dog look through the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Firefighters remove a victim from the rubble after a section of a parking garage under construction at Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • In a photo provided by Miami-Dade Fire Rescue, a rescue dog is shown in the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)(AP Photo/Miami-Dade Fire Rescue)

  • Construction workers gather near the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Rescue workers attend to a victim after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • A construction worker talks on a cell phone after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Rescue workers with dogs wait outside after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Firefighter look over the rubble after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • A firefighter looks through the rubble after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Firefighters look over the rubble after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • A parking garage under construction at a Miami-Dade College campus is shown after parts of it collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Firefighters look over the rubble after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • In a photo provided by Miami-Dade Fire Rescue, firefighters load a victim into an ambulance after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/Miami-Dade Fire Rescue)

  • A bystander looks on after a section of a parking garage under construction at Miami-Dade College in Doral, Fla., collapsed, Wednesday, Oct. 10, 2012 in Doral, killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

  • Firefighters look over the rubble after a section of a parking garage under construction at a Miami-Dade College campus collapsed, Wednesday, Oct. 10, 2012 in Doral, Fla., killing one worker and trapping at least two others in the rubble, officials said. (AP Photo/J Pat Carter)

It is not yet known what caused the garage to fall. According to CBS Miami, inspections were the responsibility of the college, not Miami-Dade County:

Inspections of the garage as it was being built, as well as permitting of the work, was performed by Miami-Dade College and not the city or county. According to the contractor’s website, the garage was designed to incorporate a shell classroom and office space on level one with parking on 5 levels above.

[MDFR Captain Louis] Fernandez said the collapse was one of the largest ever seen in Miami-Dade County and said it was a “pancake” collapse where each floor collapse onto the one below it.

Contractor Ajax Building Corporation issued a statement late Wednesday afternoon, saying the company was committed to determining the cause and extending "our deepest sympathies and prayers to the families of our colleague who died, our colleagues currently being rescued and others injured."

First responders made contact with survivors calling for help in the rubble, but had to shore up the structural integrity of the garage before sending in search crews and dogs.

"We can't just start digging through concrete," MDFR Lt. Arnold Piedrahita told the Associated Press.

The MDC campus and nearby businesses were evacuated to clear space for rescue workers and a triage area. The school declared it will stay closed for the remainder of the week.

Leslie Del Toro, who saw the garage collapse, describe on Twitter seeing one person pulled out alive: "They pulled a guy out and his whole shoulder was cut up and out of place...When I tell you every cop and fire rescue is here I mean EVERY SINGLE ONE."

Another student reported the entire campus shook when the structure collapsed.

This is a developing story and will be updated as more information becomes available.

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