SANFORD, Fla. (ABC News) -- A witness in the second-degree murder trial of George Zimmerman took the stand today to say she could hear a "boy's voice" yelling for help the night the former neighborhood watch captain killed Trayvon Martin in Sanford, Fla.
It was the first time in the trial this week that a witness has testified about who she thought was screaming for help in the fatal altercation last year.
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"I truly believe the second yell for help was a yelp," resident Jane Surdyka testified today. "It was excruciating. I really felt it was a boy's voice."
Surdyka was in her home the night Martin, 17, was shot and killed and said she could hear a "loud, dominant" voice 20 to 30 feet from where she was. She says she opened her window and could "see two people on top of the ground and one on top of the other."
George Zimmerman Jury Sees Photos of Slain Trayvon Martin Lying in Grass
Prosecutor Bernie de la Rionda then played Surdyka's emotional 911 call as Surdyka and Sybrina Fulton, Martin's mother, dabbed tears from their eyes.
During cross-examination, Surdyka described the altercation and cries for help as a life-or-death struggle.
"It was as, if nothing else, a plea for mercy?" defense attorney Don West asked.
"A plea for someone to save them," Surdyka replied.
Timeline of George Zimmerman-Trayvon Martin Case
Zimmerman contends that he was screaming that night and shot and killed the unarmed teenager after Martin repeatedly banged his head on a concrete sidewalk. Prosecutors say any screams came from Martin.
Today's second witness, Jeannee Manalo, said she also heard screams but did not know who was crying for help. She testified that she saw a man swinging.
"The one on top was moving," she described for the court as she made a punch-like gesture.
But she did not know who it was, she said.
The testimony followed a key ruling by Circuit Judge Debra Nelson that several non-emergency calls the former neighborhood watch captain made to police well before his deadly encounter with Trayvon Martin will be heard by jurors.
Zimmerman is heard asking during the calls for police to come to his subdivision and check on suspicious strangers, often black. The prosecution argued that the calls should be submitted into evidence because they show his mind-set in the days and months leading up to the shooting.
"The defendant made the calls, he created these tapes, he created these situations. He shouldn't complain," prosecutor Richard Mantei said in court.
Zimmerman's lead defense attorney said the calls were irrelevant and would confuse jurors, but Circuit Judge Debra Nelson overruled his objection today.
The ruling came as Zimmerman's neighbors continue to take the stand in day three of testimony.
The testimony and credibility of the first resident who says she heard a scuffle outside her home suffered a blow Tuesday soon after she took the stand and appeared to contradict her own previous statements to investigators and lawyers.
Selene Bahadoor Tuesday told prosecutors she was home with her sister, niece and niece's friend when she heard an unrecognizable noise. She said she heard movement outside that seemed to be going from "left to right," a different story from what Zimmerman told police.
But under questioning from Zimmerman lead defense attorney Mark O'Mara, Bahadoor agreed that this was her first time mentioning such detail. O'Mara then attempted to paint Bahadoor as compromised, using her own Facebook account against her.
O'Mara brought an open laptop to Bahahoor on the stand.
O'Mara: "Is this your Facebook? Is this your page?"
Bahadoor: "Yes"
O'Mara: "Tell me what that says on your Facebook, front page right there. Could you read that?"
Bahadoor: "Prosecute the killer of our son, 17-year-old Trayvon Martin."
O'Mara soon cut her off, snatched the laptop and backed away to his desk, seemingly dealing a blow to the state's first witness, who said she heard some of what happened that fateful Feb. 26, 1012, evening in Sanford, Fla., when Zimmerman shot Martin to death.
Zimmerman has denied the murder charge, claiming self-defense.
The case against him hinges on who confronted whom that night. But so far not a single witness claims to have seen Zimmerman and Martin's first interaction, or how their fisticuffs began, leaving prosecutors and the defense trying to build a timeline that both sides will try to poke holes into.
Significant Numbers in George Zimmerman case
Bahadoor's testimony was the culmination of a day so jarring for the parents of Trayvon Martin that both had to walk out of court.
For the first time, the items that catapulted what was then a small-town Florida shooting into a national story were displayed in court. During day two of testimony, jurors were focused intently on crime-scene technician Diana Smith's itemization of the everyday items that became iconic; the hoodie, Skittles, Arizona drink, the Kel-Tec 9 used to kill him.
Some of those items were carried dramatically before the jury in large frames encased in plastic.
During its cross of Smith, the defense methodically showed the photographs she took of a bleeding George Zimmerman: a preview of their case to be heard later.