The lawyers for a white, Hispanic Florida man who shot an African-American teenager to death allegedly in self-defense have pulled out of the case, saying they have lost contact with their client.

Attorneys Hal Uhrig and Craig Sonner said Tuesday they have not heard from George Zimmerman since Sunday despite repeated efforts to reach him.

The lawyers say Zimmerman contacted the special prosecutor's office directly without their knowledge, which attorneys advise their clients not to do.

They also say Zimmerman set up his own legal defense fund and spoke to conservative television commentator Sean Hannity, also without their knowledge.

Both attorneys say they can no longer represent a client who will not communicate with them. But they say they are concerned for Zimmerman's safety, saying he has “a bounty” on his head.

Zimmerman, a white man who led a neighborhood watch program in Sanford, Florida, last month shot and killed 17-year-old Trayvon Martin, who is black.

Zimmmerman told police he acted in self-defense when Martin attacked him. He has not been arrested. Martin's family says the young man was unarmed and was confronted because of his race. They are demanding Zimmerman be charged with murder.

A recording of an emergency telephone call to police during their confrontation is inconclusive.

The case has ignited a debate about racial tensions in the United States. Martin supporters say the shooting shows how young black men are constantly threatened with violence, while Zimmerman supporters say race had nothing to do with the killing.