The FBI announced Thursday it has joined the investigation into the disappearance of a student from the University of Florida.

Christian Aguilar, 18, hasn't been seen since the night of September 20 when he got into a fight with Pedro Bravo, a childhood friend.

Bravo is now in jail, charged with murder, even though Aguilar's body has yet to be found. Investigators say he bought duct tape and a shovel in the days before Aguilar disappeared.

The FBI's role is one of support.

"I am pleased that the FBI has confirmed to my office that the agency is indeed involved in the case of missing UF student Christian Aguilar," said Congresswoman Ileana Ros-Lehtinen, who asked for the FBI's help. "The Aguilar family and all who know Christian deserve closure on this tragically sad case. It is my sincere hope that this development will accomplish this."

Bravo has told police they got into a fight outside a local business, and Bravo left an injured Aguilar on the side of the road.

Police also seem to believe there's more to Bravo's story than what he's telling investigators.

"Of course we don't have everything from the story because if we did we'd have Christian," said Officer Ben Tobias, Spokesman for the Gainesville Police Department.

Police and volunteers from across the state have been helping in the search.

"I need help. I cannot do it by myself. If we all join together we're going to find him," said Carlos Aguilar.

Hundreds of volunteers - most of them strangers - have been combing through multiple wooded areas, while hoping to avoid the worst possible result.

For more, go to Fox-30 WAWS in Jacksonville. 

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