The search for 18-year-old Christian Aguilar has grown bigger than ever.

The University of Florida bio-chemical engineering student disappeared one week ago.

His friend, Pedro Bravo, told police they got into a fight outside a local business, and Bravo left an injured Aguilar on the side of the road last Thursay.

Bravo is now in the Alachua County Jail for failing to call for medical assistance.

Meanwhile, police from across the state are helping with the search, which will include already searched areas in light of new evidence. 

Police revealed Bravo purchased a shovel and duct tape just days before Aguilar disappeared. Now, they're searching more than 10 square miles again, this time looking below the surface.

Christian's father, Carlos Aguilar, spoke only with Action News before the search began Thursday. He says he has confidence in police, but is begging the community for help as well.

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

Mr. Aguilar says scenarios of where his son is have played over and over in his head, including the possibility that Christian disappeared on his own.

"It's possible. I hope he got disoriented - they hit him so hard that he stumbled for a few minutes, woke up and he's still around here. But that's still a concern, because why hasn't he been in the hospital?"

It's one of the many questions that are frustrating Mr. Aguilar, because he believes Predo Bravo has the answers.

"He lied to me. He lied to the police. And he admitted to doing something. It's substantial in relation to the case, that's why he's in prison."

Police also seem to believe there's more to Bravo's story.

"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.

In the meantime, hundreds of volunteers - most of them strangers - are combing through multiple wooded areas, while hoping to avoid the worst possible result.

"We're still treating this as a live search until we find some definitive evidence to leave us in another direction," said Tobias.

"I'm scared they're going to find him dead," said the teary father. "Seven days! Seven days, and nothing."

If you would like to volunteer to help in the search for Christian Aguilar, meet investigators at the Alachua County Fairgrounds anytime Thursday. It's located at on E. 39th Avenue, near the airport in Gainesville.

For more, go to Fox30-JAX.

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