A Seminole County judge has ruled that police dispatch calls George Zimmerman made in the months before he fatally shot Trayvon Martin can be admitted at his murder trial.

Judge Debra Nelson made the ruling Wednesday morning, a day after a prosecutor argued that the calls were central to the prosecution's case since they showed Zimmerman's state of mind.

Defense attorneys had objected to their use at the trial, claiming they were irrelevant.

Also Wednesday before testimony began, Judge Nelson dismissed alternate juror, identified as B72, for reasons unrelated to the case.

The juror, a 20-year-old single white man, was one of two men serving as alternate jurors in the case.  Jurors themselves, however, don't find out if they will be an alternate or serving on the six-member panel determining Zimmerman's fate until after closing arguments.

No other details were provided.

Eyewitness testifies, crime scene photos, evidence shown

On Tuesday, Zimmerman's neighbor described hearing movement from left to right behind the town-house in which she lived, and when she looked out the window she saw arms flailing and what sounded like someone saying, "No" or "Uh."

Selene Bahadoor's testimony on Tuesday at Zimmerman's murder trial was the first by a witness who saw some of the struggle between the neighborhood watch volunteer and 17-year-old Trayvon Martin. On Wednesday, other neighbors could testify about what they saw on the rainy night last year when Zimmerman fatally shot Martin in the chest during a struggle in the central Florida gated community where Zimmerman lived and Martin was visiting.

Zimmerman Trial - George Standing "I saw figures, arms flailing," Bahadoor said. "It looked like arms moving."

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Bahadoor said she left to turn off a stove and then heard a gunshot. The next time she looked out, she saw a body in the grass behind her townhome, she testified.

In cross-examining her, defense attorney Mark O'Mara accused Bahadoor of never mentioning the left-to-right movement in previous interviews. He also confronted her with a post she made on Facebook in which she "liked" a petition that championed the arrest of Zimmerman.

Zimmerman contends he lost track of Martin and was returning to his car when he was attacked. But Bahadoor's testimony appeared to suggest Zimmerman was moving away from his vehicle.

Prosecutors also may learn Wednesday whether they can introduce five police dispatch calls Zimmerman made in the six months before the shooting. Prosecutors want to use the calls to bolster their argument that Zimmerman was increasingly frustrated with repeated burglaries and had reached a breaking point the night he shot the unarmed teenager. Prosecutors played the calls for Judge Debra Nelson with the jurors out of the courtroom. The judge said she would issue a ruling after reviewing past cases.

The recordings show Zimmerman's "ill will," prosecutor Richard Mantei said.

"It shows the context in which the defendant sought out his encounter with Trayvon Martin," he said.

O'Mara argued that the calls were irrelevant and that nothing matters but the seven or eight minutes before Zimmerman fired the deadly shot into Martin's chest.

The prosecution is "going to ask the jury to make a leap from a good, responsible, citizen behavior to seething behavior," O'Mara said.

In the calls, Zimmerman identifies himself as a neighborhood watch volunteer and recounts that his neighborhood has had a rash of recent break-ins. In one call, he asks that officers respond quickly since the suspects "typically get away quickly."

In another, he describes suspicious black men hanging around a garage and mentions his neighborhood had a recent garage break-in.