* Defense seeks to keep out Zimmerman's prior calls to police
* Prosecution needs to prove Zimmerman acted with "ill will"
Florida jurors on Tuesday saw the gun that neighborhood watch volunteer George Zimmerman used to shoot unarmed black teenager Trayvon Martin and graphic pictures of Martin's body as prosecutors pressed for Zimmerman's murder conviction.
The pictures shown to the six-member, all-female jury included a close-up of the bullet hole in 17-year-old Martin's chest which prompted his father, Tracy Martin, to abandon the courtroom overcome with emotion.
At the request of the prosecution, Diana Smith, a crime scene technician, also brandished for jurors the Kel-Tec 9mm semi-automatic that Zimmerman used to shoot Martin at point-blank range.
Zimmerman, 29 and part Hispanic, was a neighborhood watch coordinator in the Retreat at Twin Lakes community in Sanford, Florida, at the time of the killing on Feb. 26, 2012. He says he killed Martin in self defense and could face life imprisonment if convicted of second-degree murder.
Smith told the court that she found no blood on the sidewalk where Zimmerman said Martin attacked him, potentially undermining his claim of self defense.
In opening statements on Monday defense attorney Don West said Martin mounted Zimmerman on the ground in mixed martial arts style "basically beating him senseless."
West said contrary to what has often been said about the case, Martin was not unarmed. "Trayvon Martin armed himself with the concrete sidewalk and used it to smash George Zimmerman's head ... That is a deadly weapon."
In its opening statement the prosecution portrayed Zimmerman as a man with a concealed weapon who committed a vigilante-style killing.
Martin was a student at a Miami-area high school and was staying at one of the homes in the gated community in Sanford when he was killed. He was walking back to the house when he encountered Zimmerman.
The killing of Martin and the decision by police not to arrest Zimmerman for 44 days sparked cries of injustice and led to civil rights protests in this central Florida town and in major cities across the United States last year.
Another witness was the first of several residents at the Retreat at Twin Lakes who had a sketchy view of the fatal encounter between Zimmerman and Martin.
Selene Bahadoor, a hospital information technology analyst, acknowledged that it was dark and rainy outside, and she couldn't see clearly through a sliding glass rear-door window in her house to the area where the shooting occurred.
But she said less than 15 seconds lapsed between the time she saw two figures standing, with arms flailing, and a gunshot that left one of the figures lying motionless on the ground.
That also appeared to contradict Zimmerman's account of a struggle in which Martin pinned him to the ground.
But a defense attorney sought to discredit her testimony noting that she had liked a 'Justice For Trayvon' Facebook page but hadn't done the same for Zimmerman's Facebook page. "The opportunity didn't present itself," Bahadoor said.
TEENAGE FRIEND EXPECTED TO TESTIFY
Prosecutors had been expected to reveal a star witness on Tuesday, the teenage girl who was talking with Martin on his cell phone in the last minutes of his life, but slow court proceedings apparently delayed her appearance.
In previous written testimony, she described Martin as scared and trying to get away from the man. She was urging him to run. She last heard Martin say, "Why are you following me?" after which she said she heard what sounded like Martin falling.
The Martin family lawyer, Ben Crump, has said her testimony further undermines the defense's argument that Martin was the aggressor.
Earlier on Tuesday the judge delayed a ruling on whether jurors could listen to telephone calls the neighborhood watch volunteer made to police in the months before he killed Martin.
Prosecutors say the calls, in which Zimmerman reported what he described as suspicious activity by black men, demonstrated "profiling" and were key to understanding the defendant's state of mind on Feb. 26, 2012 when he called police to report Martin minutes before gunning him down.
Defense attorneys have objected to the use of the tapes in the trial, calling the prior phone calls "irrelevant" and contending that they would tell jurors nothing about Zimmerman's thinking on the night he shot the 17-year-old Martin.
"They're asking this jury to make a quantum leap," said lead defense lawyer Mark O'Mara.
To win a conviction for second-degree murder, the prosecution must convince jurors that Zimmerman acted with "ill will, hatred, spite or an evil intent," and "an indifference to human life," according to Florida jury instructions.
Under Florida's Stand Your Ground law, which was approved in 2005 and has since been copied by about 30 other states, people fearing for their lives can use deadly force without having to retreat from a confrontation, even when it is possible.