Fla. teens Nicholas Presha and Jeremy Stewart were killed execution style, according to newly released evidence

(CBS/WKMG/AP) ORLANDO, Fla. - A witness says a murder suspect in the slayings of Florida teens Nicholas Presha and Jeremy Stewart told him they were shot execution style, according to evidence released Tuesday.

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Jesse Brandon Davis, 30, and Hector Manuel Rodriguez, 31, have been charged with first-degree murder and kidnapping in the deaths of the 16-year-old Presha and 18-year-old Stewart in April.

The newly released report reveals Davis' girlfriend, Angela Patterson, told authorities she walked into the house she shared with Davis and saw Rodriguez and Davis holding a white male and black male at gunpoint, reports CBS affiliate WKMG. She said the teens were naked with their hands behind their backs, according to the police reports.

A confidential informant also reportedly saw the boys being held at gunpoint, the evidence states. He told investigators he asked Rodriguez what happened to the boys and Rodriguez allegedly said, they "shot them execution-style."

Sheriff Jerry Demings said high school students Presha and Stewart met the two men intending to sell them two stolen handguns. But he says the teens were robbed and shot with at least one of the stolen guns.

The teens' bodies were later discovered by a passerby on a charred patch of grass along a popular town trail near Full Sail University.

Officials told WKMG that Nicholas is the son of Bernie Presha, an investigator for the state attorney's office and longtime former Orange County sheriff's deputy. The teens, who were best friends, attended Winter Park High School in the Orlando area.

Complete coverage of Nicholas Presha and Jeremy Stewart on Crimesider