"Today we filed an information charging George Zimmerman with murder in the second degree," Angela Corey, the special prosecutor appointed to the high-profile, racially charged case by Gov. Rick Scott, said at a news conference in Jacksonville.
"I can tell you he is within the custody of law enforcement officers in the state of Florida and he will be taken, when it's appropriate, for the appropriate appearance in front of a judge," Corey said, adding Zimmerman turned himself in after a warrant was issued for his arrest.
"When we charge a person with a crime, we are equally committed to justice on their behalf, as we are on our victim's behalf. So we are here to do that on behalf of our victim, Trayvon Martin, and on behalf of the person responsible for his death, George Zimmerman," she said.
"We do not prosecute by public pressure or by petition. We prosecute based on the facts of any given case, as well as the laws of the state of Florida."
The 17-year-old black youth was fatally shot in Sanford the night of Feb. 26 by Zimmerman, a 28-year-old white-Hispanic neighborhood watch member. Zimmerman said he acted in self-defense when he killed the unarmed Martin, who was passing through a gated community at the time, and cited the state's "stand your ground" law. Police did not charge him.
Earlier, Zimmerman's former attorneys said they stopped representing him after he contacted Florida prosecutors without consulting them and didn't return their phone calls.
"We're simply announcing that the relationship no longer exists, based on learning from the special prosecutor directly that he had contacted them," lawyer Hal Uhrig told NBC's "Today" show. "When they said we won't talk to you without your lawyers, he said, 'Well, they don't really represent me now, they were just my legal advisers so I can come in and talk to you.'"
Corey reportedly refused to talk to Zimmerman.
Uhrig said he and colleague Craig Sonner would "welcome" a call from Zimmerman.
Corey said Monday she would not take the case to a grand jury and would instead make a decision about how to move forward herself.
The decision by local authorities not to bring charges against Zimmerman set off a national outcry and led to Scott's decision to assign Corey, the state attorney for the Jacksonville area, to take over the case March 22.
The U.S. Justice Department also opened an investigation.
A grand jury previously had been set to meet Tuesday in Sanford, about 20 miles northeast of Orlando.
The lawyers said Tuesday Zimmerman also had been in touch with Sean Hannity without consulting them. Hannity, a conservative political commentator and author, recently interviewed Zimmerman's father and asked questions The Miami Herald termed "sympathetic," such as, "Is it true George mentored a black teenager?"
Zimmerman has also started a Web site, therealgeorgezimmerman.com, asking for money to deal with the "life-altering event" that, he wrote, forced him "to leave my home, my school, my employer, my family and ultimately, my entire life."
Sonner and Uhrig said they had been unaware of Zimmerman's plans to create the site. They had been working with Zimmerman's father to start a legal-defense fund in the father's name, they said.
Martin's father, Tracy Martin, scoffed at the wording of Zimmerman's site, noting that his son suffered not a life-altering event, but "a life-ending one," the Herald said.