(SANFORD, Fla.) -- A witness to the fatal encounter between George Zimmerman and Trayvon Martin appeared to place Zimmerman on top of Martin "in a position like a rider" during the moments before a gunshot ended the fight.
That testimony seemed to contradict Zimmerman's version of the confrontation with the teenager.
Selma Mora told the Florida court on Thursday that at some point she saw a man in "patterns between black and red" on top.
Zimmerman -- who has claimed Martin knocked him down, got on top and was punching him and banging his head on the sidewalk -- was wearing a red and black jacket that night.
Zimmerman, a 29-year-old neighborhood watch captain, is facing second degree murder charges for shooting and killing Martin on Feb. 26, 2012. He maintains he shot Martin, 17, in self defense.
"How were the two people positioned that you saw?" asked prosecutor John Guy.
"One of them was on the ground, and the other one was on top in position like a rider," Mora, who speaks Spanish, testified through a translator.
She is the first witness to indicate that Zimmerman was on top of Martin during the encounter.
Mora told the court that after the shooting Zimmerman was pacing and putting his hands on his head, but didn't appear to have trouble walking and didn't stagger, or stumble. Zimmerman, who has pleaded not guilty, listened intently during her testimony.
On Friday, several more witnesses to the fight are expected to take the stand to describe what they saw and heard.
The lead investigator on the case, Chris Serino, may also testify. Serino called the death of Martin avoidable and recommended manslaughter charges against Zimmerman, but his recommendation was rejected. Zimmerman wasn't arrested until more than a month after the shooting.
The witnesses are coming to the stand following two days of testimony by Rachel Jeantel. She was the woman who was talking on the phone with Martin moments before he was shot and killed by Zimmerman. She is the only person who can say that Martin was unnerved by Zimmerman, but she acknowledged on Thursday that she does not know who started the fight.
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