The lead investigator into the Trayvon Martin killing testified Tuesday that George Zimmerman told him that Martin reached for Zimmerman’s gun during a struggle, shortly before Zimmerman shot the teen.

Det. Chris Serino of the Sanford Police Department went over what Zimmerman told him about the Feb. 26, 2012, incident that led to the death of Martin, a 17-year-old unarmed black teenager.

Zimmerman said he “observed Trayvon walking between two sets of town homes and looking into a window of a town home. It was about that time that Trayvon and George made eye contact with each other,” according to Serino’s testimony.

Serino also described Zimmerman’s version of the struggle during his testimony Tuesday in Florida Circuit Court in Sanford.

“He said that Trayvon reached for the gun,” Serino said of Zimmerman. “And that’s when he freed one of his hands and got the gun.”

Zimmerman then shot and killed Martin.

Zimmerman, a 29-year-old volunteer community watchman, is facing second-degree murder charges in the death of Martin. Zimmerman contends he was acting in self-defense when he shot and killed the teen. State prosecutors claim Zimmerman’s actions constituted murder.

Serino’s testimony came a day after jurors in the Zimmerman trial heard the defendant’s recounting of the incident to the detective during a reenactment of the killing.

Zimmerman claimed that Martin was on top of him during the struggle and that the teen said, “You got me,” after being shot.

"He was on top of me. ... I shot him, and I didn't think I hit him, because he sat up and said, 'Oh, gosh, you me, you got it, you got me, you got it,'" Zimmerman said.

The Zimmerman trial is in its second week, and the prosecution is expected to wrap up its portion of the case soon.

It’s still unclear whether Zimmerman will take the stand in his own defense.