Police testify Trayvon's father said taped screams were not his son's

SANFORD, Fla., July 8 (UPI) -- Trayvon Martin's father said screams heard in a taped 911 call were not those of his son, witnesses said in George Zimmerman's murder trial in Florida Monday.

Who made the screams, Zimmerman, the self-acknowledged shooter, or Trayvon, the 17-year-old victim, in the seconds before Trayvon was fatally wounded, has been a point of contention in the second-degree murder case in Sanford. Zimmerman maintains he killed the youth in self-defense after encountering him in a gated community the night of Feb. 26, 2012.

Chris Serino, the lead investigator for the Sanford Police Department, played for the jurors the audiotape he had previously played for Tracy Martin, the slain teen's father, in the days after the shooting, and noted the father said the screams were not Trayvon's.

"I heard it, and saw the movement of his mouth," Serino said of Tracy Martin's "no" in a subdued voice, adding the father seemed very emotional.

The defense also called Doris Singleton of the Sanford police, who was present during Serino's interview with Tracy Martin. She described Martin as "very upset," and hanging his head and crying.

Adam Pollock, a gym trainer, also testified Monday, saying Zimmerman trained at his gym but was still a novice at the time of the shooting. Pollock said Zimmerman was "soft" and "non-athletic," obese and seeking to lose weight, and never entered the gym's boxing ring.

Pollock demonstrated the "ground and pound" fighting position in court. Jurors previously heard from a Zimmerman neighbor who said he saw Trayvon Martin atop Zimmerman in that position during their fight, the Orlando Sentinel reported.

The first witness called Monday was Sondra Osterman, a friend and former co-worker of Zimmerman's, who said she was certain the voice screaming before the fatal shot, captured on a neighbor's 911 call, was that of Zimmerman.

"Yes, definitely, it's Georgie. I hear him screaming," Osterman testified.