GAINESVILLE, Fla. -

Jurors in the Pedro Bravo murder trial are hearing from more detectives who investigated the disappearance of a University of Florida freshman.

Tuesday's testimony started with a detective who led a team of as many as 20 officers in their September 2012 search efforts to find Christian Aguilar.

Bravo, then 18 years old, had already been interrogated by Gainesville police for several hours before detectives tried to corroborate versions of his story.

Aguilar was last seen alive with Bravo.

Investigators examined cell phone records and surveillance video to get an idea if Bravo was being truthful.

"The reason I was looking north on 13th Street was because Walmart is located south and that was the information we had received -- that he had driven north and (I) did not see it," said Ray Barber, a now-retired detective sergeant with the Gainesville Police Department.

"Did you see anything that matched his vehicle," asked prosecutor Brian Kramer.

"No," replied Barber.

Bravo and Aguilar were friends from Doral Academy in South Florida, where they got to know Erika Friman.

All three wound up in Gainesville for college, and Bravo was upset that Aguilar was dating Friman, who dated Bravo first.

Prosecutors believe Bravo was so obsessed with getting his ex-girlfriend back that he plotted to poison and kill Aguilar.

The 18-year-old's body was found in a shallow grave three weeks after he was reported missing. Hunters looking for firewood in Levy County made the discovery.

Police found blood in Bravo's SUV and Aguilar's book bag, containing all of his identification, inside of Bravo's closet.

Bravo initially told police he was only in a verbal argument with Aguilar but later changed his story. Police said Bravo told them the two had a violent fight and Bravo dropped off Aguilar on the side of the road, injured but alive.

Defense attorneys said Bravo did not kill his friend and blames his varying stories to police on medication.

"You understand that he was under medication at the time," asked defense attorney Michael Ruppert.

"I have no knowledge of that," said Barber. "I know he was there. I don't know what medication he was taking."

"And you didn't inquire?" asked Ruppert.

"No sir," replied Barber.

Also shown in court were cellphone records that triangulated Bravo's movements on the day he fought with Aguilar, as well as a photograph of what Bravo searched on his iPhone.

"I need to hide my roommate" was a search term on Bravo's phone.

Swamps and reservoirs were listed as options.

Follow Terrell Forney on Twitter @TVTerrell

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