Sanford, Fla., Police Chief Bill Lee, who drew criticism for his department's handling of the killing of Trayvon Martin, was fired Wednesday, his spokeswoman said.

Spokeswoman Sara Brady told CNN that Sanford City Manager Norton Bonaparte made the decision.

Lee had submitted a resignation letter to the city commissioners in April, but they voted not to accept it.

In March, the chief had said he was stepping down temporarily amid public outrage the police failure to arrest George Zimmerman, the neighborhood watch volunteer who has said his shooting of Martin on Feb. 26 was an act of self-defense.

Also Wednesday, the Seminole County Sheriff's Office released 911 tapes of calls placed the morning after the shooting, when police had still not identified Martin, 17, as the victim. He was unarmed and carrying no identification when he was shot while walking to his father's girlfriend's house after picking up some snacks at a nearby store.

In the first call, Trayvon's father, Tracy Martin, calls police at 8:39 a.m. asking to file a missing persons report, which typically would not be accepted until 24 hours after a person has been discovered missing. It hasn't really been 24 hours, he tells the police dispatcher. But I'm from Miami and my son's up here with me ... he don't know anybody up here.