May 17, 2012 -- Two police reports written the night that George Zimmerman shot Trayvon Martin said that Zimmerman had a bloody face and nose, according to police reports made public today.

The reports also note that two witness accounts appear to back up Zimmerman's version of what happened when they describe a man on his back with another person wearing a hoodie straddling him and throwing punches.

It has been such a contentious case that even the evidence is being disputed.

The police report states that Trayvon Martin's father told an investigator after listening to 911 tapes that captured a man's voice frantically callling for help that it was not his son calling for help.

But Tracy Martin, Trayvon's father, claims that is not true. The Martin family lawyer Ben Crump told ABC News that Tracy Martin initially listened to a distorted version of the 911 calls and said he could not identify the voice. But when he listened to a second tape that had been "cleaned," "He immediately broke down in tears because he knew it was his son calling for help," Crump said.

The new information is part of a trove of documents released by the Florida State Attorney today in the case against Zimmerman, who is charged with second degree murder for the Feb. 26 killing of Martin, an unarmed 17-year-old African American male.

Surveillance video of Martin in a store purchasing skittles right before the fatal incident was also released today.

Zimmerman, 28, is a multi-racial Hispanic man who volunteered for the neighborhood watch committee who claimed that he shot Martin in self-defense after the 6-foot tall, 160 pound teenager knocked him to the ground, banged his head against the ground and went for Zimmerman's gun.

The documents start with a criticism of Zimmerman's decision to follow the teenager, who Zimmerman said was looking suspicious.

"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," an investigating officer wrote.

Zimmerman claims he got out of his vehicle to find a house number to let police know where he saw the allegedly suspicious person, and while returning to his car was knocked down by a punch in the nose and attacked by Martin.

Two police officers reported that when they arrived at the scene of the shooting, Zimmerman seemed to have a battered nose and bloodied face. One wrote that his "facial area was bloodied," and the back of his clothing was soiled with wet grass.

"Zimmerman was also bleeding from the nose and the back of his head," Officer Ricardo Ayala wrote.

Another officer wrote, "I saw that Zimmerman's face was bloodied and it appeared to me that his nose was broken."

Witnesses, whose names were redacted from the report, also lent support to Zimmerman's version of what happened.

"He witnesses a black male, wearing a dark colored 'hoodie' on top of a white or Hispanic male and throwing punches 'MMA (mixed martial arts) style,'" the police report of the witness said. "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 male wearing the hoodie) laid out on the grass."

A second witness described a person on the ground with another straddling him and throwing punches. The man on the bottom was yelling for help, the witness told police.

The documents state that Zimmerman can be heard yelling for help 14 times on a 911 call recorded during the fight.

Yet another witness described the confrontation in emotional terms.

The witness heard "someone yelling, almost crying. Then I heard a gunshot." The witness wrote that he or she "saw a man on top of a guy laying on the ground. He was putting his hands on his neck or chest."

The man asked the witness to call 911.

"He stood up and took a couple steps away and put his hands on his head and then walked back over to the guy on the ground. He looked at him for a minute, then started to walk away toward the road. That is when the police walked up," the witness wrote.

The lead investigator on the case, Officer Christopher Serino, wrote that Zimmerman could be heard "yelling for help as he was being battered by Trayvon Martin."

Martin's death sparked public outrage after police released Zimmerman without any criminal charges for the killing. Zimmerman was later charged with second-degree murder, and the killing provoked widespread debate about racial profiling.

The autopsy also shows that Zimmerman shot Martin from a distance of between 1 inch and 18 inches away, bolstering Zimmerman's claim that he shot Martin during a close struggle.

Martin's autopsy report also revealed that there was a quarter-inch by half-inch abrasion on the left fourth finger of Martin, another indication of a possible struggle.

The teen, who lived in Miami, was in Sanford while serving a suspension for an empty marijuana bag discovered in his possession. Martin had THC, the drug found in marijuana, in his blood on the night of his death, according to the autopsy. His family told ABC News that it was "trace amounts" of THC.