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Emergency crews in Irving, Texas, responded Thursday morning to a major bus crash on the northbound side of State Highway 161, NBC DFW reports.
At least two people died in the accident, a state trooper told the Associated Press.
The vehicle flipped onto its side, forcing authorities to shut down all lanes of the highway, according to KWTX.
Approximately 40 elderly people were trapped inside the charter bus, which was transporting the retired people to a gambling outing at the Choctaw casino in Oklahoma, according to USA Today.
"There was obviously a lot of pain," a witness who helped pull victims from the wreckage told NBC DFW. "You had to start with whoever was on top, try to untangle them. People were just screaming."
The bus belongs to the Cardinal Coach LInes of Mansfield, Texas.
The stretch of State Highway 161, also known as the President George Bush Turnpike, is located approximately 15 miles outside Dallas.
More from the Associated Press:
By DAVID WARREN AND JOHN L. MONE
IRVING, Texas — At least two people were killed and about three dozen were hospitalized after a charter bus careened off a Texas highway and flipped onto its side Thursday, drawing a large emergency response as rescue crews struggled to reach victims inside, authorities said.
The Cardinal Coach Line bus was traveling just east of Dallas/Fort Worth International Airport in Irving when it suddenly weaved across the busy highway, struck a concrete barrier and toppled over into the center median, witnesses said. The cause of the accident was not immediately clear.
"We ended up swirling and weaving and then ended up on the side," passenger Daniel Risik, 73, told The Dallas Morning News. "People were screaming and hollering, a very traumatic situation to say the least."
The bus, which was carrying about 45 people, was headed to a casino in Oklahoma, officials said. Risik said most people aboard the bus weren't wearing seat belts.
"People were piled on top of each other," he said. "It was unbelievable. A lady had pinned me. Rescue got there and started pulling people out of a roof emergency hatch. People were hollering, screaming, there was blood all over the place. It was unbelievable."
Texas Department of Public Safety Trooper Lonny Haschel confirmed that two people were killed. About three dozen people were being treated at local hospitals, many of them suffering from fractured bones, hospital officials said.
Emergency vehicles could be seen swarming the bus as it lay in the grassy center median along the President George Bush Turnpike. Ladders were being used to pull passengers from some broken windows. Witnesses said one person appeared to be pinned by the bus which picked up passengers in Fort Worth.
A man who answered the phone at Cardinal Coach's offices in Mansfield, just south of Dallas, confirmed that one of the company's buses was involved in the Irving accident. But said he didn't have time to talk because he was trying to gather information about the crash.
Cardinal Coach has reported no crashes in the last two years that resulted in deaths or injuries, according to the Federal Motor Carrier Safety Administration. The company operates five buses and employs seven drivers, records show.
Law enforcement officers were interviewing bus passengers and other drivers who witnessed the crash. Haschel said he had no immediate information on where the bus trip originated.
A spokeswoman for Baylor Medical Center in Irving said 13 patients arrived at the hospital following the accident. Officials at Las Colinas Medical Center in Irving confirmed another six patients were there, though details weren't immediately available on their conditions.
Another 11 patients were transported to Parkland Memorial Hospital, including the driver of the bus, and another victim was airlifted to a fourth hospital in critical condition, hospital officials said.
Public transportation buses with Dallas Area Rapid Transit were used to transport some passengers with lesser injuries.
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