Police released Monday neighborhood watchman George Zimmerman's account of on why he shot Trayvon Martin one month ago, claiming that the slain 17-year-old punched him in the face and slammed his head into the sidewalk.

According to the Orlando Sentinel, Zimmerman said he was walking toward his SUV on February 26 when Martin approached him from behind and attacked him after the two exchanged words. Zimmerman and his lawyer said he shot Martin in self-defense.

Police indicate in their details that Zimmerman called them to report Martin as a suspicious person and followed him before the two met face-to-face, as the widely heard 911 tapes describe. Police are unsure about what took place between Zimmerman's call to them and the shooting, but said their evidence found that Zimmerman was crying for help. Lawyers from Martin's family said the cries came from the teenager.

Martin's parents and lawyer have said that Zimmerman, who is still free, should be arrested for pursing Martin despite police urging Zimmerman not to follow him on the 911 tapes.

The Martin family confirmed to the Associated Press Monday a report that their son was suspended from school for carrying a bag of marijuana in his book bag.

"We maintain that regardless of the specific reason for the suspension, it's got nothing to do with the events that unfolded on Feb. 26," spokesman Ryan Julison said.

The late teenager's parents and lawyers claim Martin's suspension and the public push back by Zimmerman's lawyer and supporters are designed to denigrate their son's image.