Newly released video shows Zimmerman's account of fatal Trayvon Martin fight

A newly released video shows a U.S. neighborhood watch volunteer standing at the scene of the fatal shooting of an unarmed black teen and giving police a detailed account of their fight in a case that led to a national outcry over race and self-defense laws.

In a video posted on a website by George Zimmerman's defense team, Zimmerman said Trayvon Martin saw his gun and reached for it as the two scuffled on the sidewalk at a gated apartment community in Florida. That's when Zimmerman said he pulled the gun and shot the teenager.

The tape shows two bandages on the back of Zimmerman's head and another on his nose.

On the tape, Zimmerman reenacts the scuffle with Martin in the moments before he shot the 17-year-old. Zimmerman said Martin kept "slamming and slamming" his head on the sidewalk.

"It felt like my head was going to explode," he said.

Zimmerman wasn't arrested or charged for weeks after the shooting, leading to protests across the U.S. He has since been charged with second-degree murder. He claims he shot the teen in self-defense under Florida's "stand your ground" law.

The Sanford police chief, Bill Lee, was fired Wednesday over his department's initial investigation into the shooting.

Zimmerman told police the confrontation began when he saw Martin walking toward him on the evening of Feb. 26.

Zimmerman had already called police after spotting the teen in the neighborhood. The teen was walking back to a friend's home after going to a nearby convenience store, but Zimmerman thought he looked suspicious and followed him.

Officials released a transcript of the 911 call Wednesday.