Christian Aguilar's Backpack, Blood Stains Led To Pedro Bravo Murder Charges: Police (PHOTOS, VIDEO)

09/30/2012 09:12 am ET | Updated Nov 30, 2012

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Among evidence used to charge Pedro Bravo with the murder of his friend Christian Aguilar was the discovery of the missing University of Florida student's backpack, hidden inside a suitcase in Bravo's closet.

Gainesville Police detectives also discovered blood in Bravo's SUV, and a receipt showing he paid cash for a shovel and duct tape days before Aguilar was last seen September 20 was found lying on top of his dresser, according to an arrest report.

State Attorney Bill Cervone told the Gainesville Sun that while the lack of a body is unusual for first-degree murder charges, circumstantial evidence was strong enough to charge Bravo.

"The ordinary murder case starts with the discovery of a body and works backward. This isn't ordinary, but it is legally permissible to prosecute for murder in the absence of a body," Cervone said. "It requires circumstantial evidence proving death and I believe we have that."

Bravo and Aguilar, both 18, graduated Doral Academy in Miami before moving to Gainesville this summer. Aguilar began taking classes at UF, and Bravo and his former girlfriend from Doral, Erika Friman, enrolled at Santa Fe College.

But Aguilar began dating Friman, and Bravo told police the two got into a fight about it on the night of Thursday, September 20, several hours after they were last captured by surveillance cameras buying a CD at a local Best Buy.

Bravo told police that after punching Aguilar in the face, forcing him out of his SUV, and then beating him for another 10-15 minutes, he left his friend injured and unconscious by the side of a road.

According to the arrest report:

[Bravo] stated that the victim was barely breathing and not moving, lying on his back partially in water, at the time the def. left him.

The def. stated that he turned the victim's cellular telephone off and then threw the victim's cell phone into the wooded/water covered area, prior to returning to his residence.

Searchers have scoured this area and others, but have so far found no trace of Aguilar or his red-covered cell phone. Researchers from UF's Institute of Food and Agricultural Sciences determined dust on Bravo's Chevy Blazer is lime rock, prompting police to ask residents with lime rock driveways and roads to check their property for disturbed ground.

Police are rushing tests that will determine if blood found in several locations in the vehicle is Aguilar's.

Bravo appeared in court Saturday morning, where he was denied bond. According to the Miami Herald, a family friend read a statement from Aguilar's father, Carlos, before the hearing.

"The Aguilar family extend their condolences to Pedro Bravo's family," the statement read. "They understand that there are two families suffering today. That being said, they do ask that justice be served."

Bravo's attorney told the Herald his client has remained silent about the case since an initial interview with police.

Christian Aguilar Missing In Gainesville