SANFORD, Fla. -- Trayvon Martin's fatal encounter with George Zimmerman was "avoidable," and the teen was not doing anything criminal at the time of their confrontation on Feb. 26, a report by Sanford, Fla., police says.
The report, dated March 13, came nearly a month before a special prosecutor brought second-degree-murder charges against Zimmerman, 28, in the death of 17-year-old Trayvon. He has pleaded not guilty and said he acted in self-defense.
MORE: Documents, Photos Released in Zimmerman Case
"The encounter between George Zimmerman and Trayvon Martin was ultimately avoidable by Zimmerman, if Zimmerman had remained in his vehicle and awaited the arrival of law enforcement, or conversely, if he had identified himself to Martin as a concerned citizen and initiated dialog in an effort to dispel each party's concern," the report says. "There is no indication that Trayvon Martin was involved in any criminal activity at the time of the encounter."
A large cache of reports, documents, photos and other descriptions of evidence in the case were released to the public Thursday evening after being disclosed previously to defense attorneys. The case has attracted worldwide attention with accusations by Trayvon's family and civil rights leaders that Zimmerman, who is Hispanic, targeted Trayvon because he was black and said he appeared to be "up to no good."
The report says a single bullet perforated Trayvon's heart.
Other police investigative reports said that Trayvon had been staying in the gated residential complex for a week before the shooting and that he had been sent to the home of a friend by his father after the teen had been suspended from school for 10 days for marijuana possession. A toxicology report on his body found a small amount of THC, the psychoactive chemical in marijuana, in his blood.
A police report concluded that at the time he was confronted by Zimmerman, Trayvon "was in fact generally running in the direction of where he was staying as a guest in the neighborhood."
Zimmerman had reported "suspicious persons, all young black males" to police on three previous occasions in 2011, the reports said.
"According to record checks, all of Zimmerman's suspicious person calls while residing in the Retreat neighborhood have identified Black males as the subjects," the report said.
Witness accounts in the police reports describe the confrontation. One witness reported seeing Trayvon on top of Zimmerman, hitting him in a physical struggle.
According to a report by Christopher Serino of the Sanford Police Department, a witness said she heard "a commotion, which sounded to her like arguing." She looked out from her bedroom window and saw two men on the ground.
"She then heard someone yell 'help, help,' " the report said. "She then heard a 'pop' noise and then saw the decedent laying on the ground, motionless, and the other male, who she described as 'larger' and 'Hispanic looking,' standing over the decedent."
Another witness interviewed on the night of the shooting described hearing a commotion and going out to investigate, the same report said:
"He witnessed a black male, wearing a dark colored 'hoodie' on top of a white or Hispanic male who was yelling for help. He elaborated by stating the black male was mounted on the white or Hispanic male and throwing punches 'MMA (mixed martial arts) style.' He stated he yelled out to the two individuals that he was going to call the police. He then heard a 'pop.' He stated that after hearing the 'pop,' he observed the person he had previously observed on top of the other person (the black male wearing the 'hoodie') laid out on the grass."
Serino's report described his review of the 911 calls: "In the background I could clearly hear a male's voice yelling either 'Help' or 'Help Me,' fourteen (14) times in an approximately 38 second time span. This voice was determined to be that of George Zimmerman, who was apparently yelling for help as he was being battered by Trayvon Martin."
Officer Jonathan Mead recognized Zimmerman as the neighborhood watch head. "Zimmerman appeared to have a broken and bloody nose and swelling of his face," Mead said.
Another officer reported taking a photo of Zimmerman's injuries with his personal phone. The documents released include a photo of Zimmerman with what appears to be blood coming from his nose.
Officer Timothy Smith said EMTs treated Zimmerman for his injuries at the scene, and he declined to go to a hospital.
On the way to the police department, Zimmerman complained that his head hurt and he felt lightheaded but declined medical attention, Smith said.
Among the evidence was an audio interview of Zimmerman's father, Robert, in the Seminole state attorney's office March 19. The father, under oath, said the person crying for help on the 911 tape is "absolutely, positively George Zimmerman."
"That was George, and he was not just yelling, he sounded like he was screaming for his life," the elder Zimmerman said.
In a report, Serino said that on Feb. 28, he played the 911 tapes for Tracy Martin, Trayvon's father. "I asked Mr. Martin if the voice calling for help was that of his son. Mr. Martin, clearly emotionally impacted by the recording, quietly responded 'no.' "
Serino said that he did not record that interview with Tracy Martin but that another officer was present.
A report from the FBI's Digital Evidence Laboratory on the 911 calls on the night of the shooting said "the screaming voice of the 911 call is of insufficient voice quality and duration to conduct meaningful voice comparison." It said poor recording quality and a weak signal left experts unable to determine whether Zimmerman had uttered what some perceived to have been a racial slur.