Florida State law professor Dan Markel was shot twice at close range by Sigfredo Garcia on July 19, 2014, in a murder-for-hire plot that Garcia's sometimes girlfriend Katherine Magbanua helped arrange, according to testimony from a key prosecution witness.

Luis Rivera on Tuesday told a Tallahassee, Florida, jury that he and his childhood friend Garcia were paid to travel from Miami to Tallahassee to kill the law professor so that Markel's ex-wife Wendi Adelson would be able to relocate to South Florida with the couple's two children—a move the former spouses had wrangled over in court. Garcia and Magbanua are standing trial for first-degree murder, while Rivera in 2016 pleaded guilty to second-degree murder. He received a seven-year sentence in exchange for cooperating with prosecutors. (Rivera, who was a leader of the Latin Kings gang in Miami, is currently serving 12 years in a federal prison on racketeering charges, with the second-degree murder sentence to run concurrently.)

Dan Markel.

"He said, 'We're going to have to kill a man for some kids,'" Rivera testified, dressed in a dark blue prison uniform. "Because the lady wants her kids back."

Rivera told the jury that Garcia shot Markel twice at close range while the professor was seated in his car and that he remained behind the wheel of the rented Prius during the shooting. Rivera said that he was paid $35,000 for his role in the shooting, with Garcia receiving $40,000 and Magbanua receiving the remainder of the $100,000 payment.

But Rivera said he didn't have any contact with members of the Adelson family, whom prosecutors allege hired Rivera and Garcia to kill Markel, with Magbanua acting as a go-between. (Prosecutors have said they believe Wendi Adelson's brother and mother—Charlie and Donna Adelson—were behind the plot, though no members of the Adelson family have been charged in connection with Markel's death. Magbanua dated Charlie Adelson around the time of the murder. Wendi Adelson testified under immunity Friday and denied any involvement or knowledge of a plot to kill her ex-husband.)

During cross-examination, Garcia's defense attorney Saam Zangeneh worked to discredit Rivera, highlighting his longtime, high-up involvement in the Latin Kings gang. Magbanua's attorney has not yet had a chance to cross-examine Rivera.

During his opening statement Thursday, Zangeneh, alleged that Rivera was hired directly by Charlie Adelson to kill Markel, and that Rivera had sold drugs to Charlie Adelson.

Earlier in the day, the jury heard testimony from Jeffrey Lacasse, a Florida State professor who was dating Wendi Adelson at the time Markel was killed. Lacasse testified that Wendi told him that her brother, Charlie Adelson, had looked into "all options" for getting the couple's children to move to South Florida, including having him killed. Wendi Adelson was bitter towards Markel and has an extremely close relationship with her family, Lacasse testified. Lacasse was initially a suspect in the murder, but was cleared after police confirmed that he was out of the state at the time of the killing.