The embattled police chief at the center of a fatal neighborhood watch shooting temporarily stepped down Thursday, saying he had become a distraction to the investigation.

Sanford Police Chief Bill Lee has been heavily criticized after his officers decided not to arrest George Zimmerman, a neighborhood watch volunteer who shot an unarmed black teen to death on Feb. 26.

"As a former homicide investigator, a career law enforcement officer and a father, I am keenly aware of the emotions associated with this tragic death of a child. I'm also aware that my role as a leader of this agency has become a distraction from the investigation," Lee said.

The shooting has sparked several protests, and city commissioners gave the chief a "no confidence" vote on Wednesday night.

Zimmerman claims the shooting was self-defense. He told police 17-year-old Trayvon Martin attacked him after he had given up on chasing the teenager and was returning to his sport utility vehicle.

The police chief has said authorities were prohibited from making an arrest based on the facts and circumstances they had at the time of the shooting. He said he continued to stand behind his agency's investigation.

"I must temporarily remove myself from the position as police chief for the city of Sanford. I do this in the hopes of restoring some semblance of calm to a city which has been in turmoil for several weeks," he said. "It is my hope that the investigation will move forward swiftly and appropriately through the justice system and that a final determination in this case is reached."

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