MIAMI — The legal team for George Zimmerman, who is charged with second-degree murder in the killing of Trayvon Martin, has released Zimmerman's written statement and several audio and video interviews with law-enforcement investigators in which Zimmerman says that he was ambushed and hit so violently by Martin that his head "felt like it was going to explode" and that the teenager had covered his nose and mouth before reaching for Zimmerman's firearm.

The material represents the first time the public has had the opportunity to hear Zimmerman's initial statements to police about the shooting of Martin, 17, an unarmed African American.

Martin's death Feb. 26 in Sanford, Fla., and the decision by the local police not to immediately bring charges against Zimmerman, who is Hispanic, set off a national outcry about race and Florida's self-defense laws.

As part of the case's continuing fallout, Bill Lee, Sanford's police chief, who had been criticized for his handling of the investigation, was fired this week.

The information released late Wednesday on a website established by Zimmerman's lawyer, Mark O'Mara, includes video of Zimmerman being interviewed the day after the shooting. He has two bandages on the back of his head and said he had difficulty breathing because his nose had been broken.

Zimmerman appears relatively relaxed. Throughout the recordings, he responds to questions using "sir" or ma'am."

O'Mara had sought to keep the statements, audio and video sealed from the public, but the judge in the case ordered them released because Zimmerman had not confessed to a crime.

Chris Serino, the Sanford Police Department's lead investigator on the case, is heard in one recording repeatedly warning Zimmerman, 28, that public opinion, already tilting against the crime-watch volunteer, would pillory him unless he could explain exactly why he felt justified in pulling the trigger at a "kid with a future."

Martin was no thug, Serino told Zimmerman: He was an athlete. His parents cared about him. He had no violent history, and he was armed with only a pack of candy and a bottle of iced tea.

"This 17-year-old boy was one of those kids who would have been a success story," Serino said.

As Zimmerman retells his version of events recorded in the days after the shooting, the story remains essentially consistent, although some of the language varies.

In one of the videos, Zimmerman is seen re-enacting the episode for police. He also gives investigators a tour of the neighborhood.

Zimmerman, who is in jail in Florida, had been released on a bond of $150,000 after a hearing April 20.

But the judge in his case, Kenneth Lester Jr., revoked the bond for Zimmerman on June 1 and returned him to jail after prosecutors accused Zimmerman and his wife, Shellie Zimmerman, 25, of lying about their assets in court.