Undated handout photo released by the Martin family public relations representative shows 17-year-old Trayvon Martin.
Undated handout photo released by the Martin family public relations representative shows 17-year-old Trayvon Martin.

The lawyer for the family of an African-American teenager shot and killed by a neighborhood watch volunteer in the southeastern U.S. state of Florida says they have information disputing the man's claim that he shot the boy in self-defense.

Benjamin Crump told reporters Tuesday that records of calls from Trayvon Martin's mobile phone shows the boy was talking to his girlfriend moments before last month's fatal shooting.  Crump says he learned from the girl that Trayvon noticed he was being followed as he was walking back home from a convenience store near Orlando.   

According to the lawyer, Trayvon, 17, ran away at his girlfriend's urging, and managed to briefly evade the man.  The girlfriend urged Trayvon to run again, but the teenager said he was just going to walk fast.  Trayvon then asked the man why he was following him, followed by the older man demanding to know what Trayvon was doing in the neighborhood.  A few minutes later, Crump says the girl heard what sounded like Trayvon being pushed, followed by an altercation, before the phone cut off.  

Moments later, police arrived on the scene to find Trayvon had been shot by George Zimmerman, who had called emergency personnel before the shooting to report a suspicious person in the neighborhood that turned out to be Trayvon.  

But Crump says Zimmerman's claims do not hold up under the girl's recollection.

"Never in any account other than George Zimmerman, this neighborhood association 'loose cannon,' does anybody say that Trayvon Martin was up to no good, that he seemed high, or anything," noted Crump, "and in fact, this young lady details completely the tone of the conversation and the nature of the conversation, and what was happening the last minutes of his life."

Prosecutors in Florida say they will convene a grand jury to investigate the incident and the U.S. Justice Department says its civil-rights division is opening an investigation.  

Zimmerman has not been arrested by local police, which has sparked increasing nationwide outrage.  An online petition posted by the website Change.org has gathered more than 700,000 signatures demanding his arrest.

Another online campaign on the social network Facebook is calling for a "Million Hoodies March" for Wednesday in New York City in honor of the slain teenager.  The title refers to the hooded sweater Trayvon was wearing when he was killed.  

The announcement said "A black person in a hoodie is not automatically 'suspicious.' "

The incident has also drawn attention to so-called "stand your ground" laws in Florida and several other states, which allows people to confront a potential attacker with deadly force if they feel their life is in danger.    

Some information for this report was provided by AP.