George Zimmerman is being charged with second-degree murder for the killing of Trayvon Martin, Florida State Attorney Angela Corey has announced.

Zimmerman, 28, has claimed he acted in self-defense Feb. 26 when he shot 17-year-old Trayvon in Sanford, Fla. The neighborhood watch activist told a 911 operator that Trayvon was acting suspiciously. He got out of his SUV and followed him, although the dispatcher told him to stay in his vehicle and wait for police. A confrontation ensued, and Trayvon was shot once in the chest.

Zimmerman had been in hiding and has not spoken publicly since the shooting. Tuesday, two attorneys withdrew as his counsel after they learned he had contacted Corey's office and news media without their knowledge. They said they had lost contact with him Sunday.

Monday, Zimmerman launched a website to collect donations he said would be used "only for living expenses and legal defense."

TIMELINE: The Trayvon Martin case

Update at 8:59 p.m. ET: Here is Zimmerman's booking photo from the Seminole County jail, officially the John E. Polk Correctional Facility.

He was arrested by the Seminole County Sheriff's Office at 8:30 p.m. ET. His first court appearance is scheduled for Thursday at 1:30 p.m. ET. Until then, as the sheriff's department notes, "Inmate may not be bailed."

His jail record lists an "account balance" of $121. No indication what that's for.

His date of birth is listed as Oct. 5, 1983.

Update at 8:38 p.m. ET: George Zimmerman has arrived at the Seminole County jail in Sanford, according to news reports.

Update at 7:46 p.m. ET: The man who prosecuted notorious serial killer Ted Bundy told USA TODAY's Marisol Bello that a judge could possibly throw out the case under Florida's "stand your ground" law, which has been at the center of the killing. Zimmerman has claimed he acted in self-defense, telling police Trayvon attacked him.

George Dekle, now a University of Florida law professor, said Zimmerman's attorney can seek a hearing to determine if Zimmerman is entitled to immunity from prosecution. If a judge finds that the evidence insufficient to show that Zimmerman acted in any way other than self-defense, he can dismiss the case.

"This is no fun case for a prosecutor," Dekle said. "You will get one group of people or another after you like a pack of wolves… No matter what happens, you are going to get toasted."

Dekle said he has known Corey for 25 years and if she charged 2nd-degree murder, then she must feel confident she has the evidence.

"I don't know what the evidence is but I know Angela Corey," he said. "She has a reputation that is well-deserved as a very good prosecutor who is unafraid to prosecute cases vigorously and unafraid to say no to a case if she feels she does not have the evidence."

He said bond will be set for Zimmerman in the next 48 hours and it is likely that he can walk out again because he has shown he is not a flight risk.

If the case does go to trial, he said, the challenge will be finding jurors who don't know anything about the case or have not been swayed by media coverage.

"It shrinks the jury pool," he said.

Update at 7:39 p.m. ET: USA TODAY's Marisol Bello has filed this from a news conference by Zimmerman's new legal counsel:

During a press conference, Mark O'Mara, Zimmerman's new lawyer, said his client is troubled by everything that's happened. "I can't imagine living in George Zimmerman's shoes the last few weeks," he said. O'Mara said he told Zimmerman to "stay calm and listen to my advice." He said Zimmerman is in custody. He said they are not yet in the same geographic area, but expects that to happen tonight. "Let the process work, let's not prejudge anyone any longer," he said. "There are high emotions. … But let the process work." He said Zimmerman will likely remain in protective custody. "He is a client who has a lot of hatred focused on him," he said. He said he wants Zimmerman out on bail "because I need him out for the defense." "I hope he gets a bond but that's up to a judge." "I think they would be better off if they had not charged him."

Update at 7:27 p.m. ET: Zimmerman will plead not guilty, says his new attorney.

Update at 7:09 p.m. ET: Trayvon Martin's parents said they are relieved that Zimmerman has been arrested.

"We have faith and hope in Ms. Corey's office,''said Sybrina Fulton, Trayvon's mother. "We are not the experts. They are the experts. We put our faith in them."

Trayvon's father, Tracy, said, "It feels good to know that he is off the street, that he is in custody.''

In an interview with the Associated Press before the announcement, Fulton said that if she could speak with Zimmerman, "I would probably give him an opportunity to apologize. I would probably ask him if there were another way that he could have settled the confrontation that he had with Trayvon, other than the way it ended, with Trayvon being shot."

Tracy Martin, offered several questions that he would like to ask Zimmerman, especially, "Was it really worth it?"

"The question I would really like to ask him is, if he could look into Trayvon's eyes and see how innocent he was, would he have then pulled the trigger? Or would he have just let him go on home?"

Update at 6:58 p.m. ET: Read the charging document, called an issue capias, and Corey's statement from the news conference.

Update at 6:47 p.m. ET: Corey said the decision to charge Zimmerman was made last week, USA TODAY's Marisol Bello reports.

Update at 6:27 p.m. ET: Here's background about second-degree murder in Florida:

To prove second degree murder, a prosecutor must show that the defendant acted according to a "depraved mind" without regard for human life. Florida state laws permit the prosecution of second degree murder when the killing lacked premeditation or planning, but the defendant acted with enmity toward the victim or the two had an ongoing interaction or relationship. Unlike first degree murder, second degree murder does not necessarily require proof of the defendant's intent to kill. ... Florida uses this law to deter and punish unintended deaths as a result of felonious activities.

Some defenses:

Justifiable use of deadly force to defend against a felony committed against a person or property. Excusable homicide committed by accident. Spontaneous or negligent killing that might qualify as manslaughter instead of murder.

If convicted of second-degree murder, which is a first-degree felony, Zimmerman could be sentenced to prison for up to 30 years, though Florida also permit prosecutors to seek life.

Update at 6:24 p.m. ET: Corey has ended her news conference.

Update at 6:19 p.m. ET: Zimmerman will appear before a judge within 24 hours in Seminole County.

Update at 6:17 p.m. ET: CNN reports that Mark O'Mara, a veteran attorney in central Florida, will now represent Zimmerman.

Update at 6:11 ET: Zimmerman is in Florida, Corey says, and "may have obtained new counsel within the past couple of hours."

Update at 6:08 p.m. ET: Corey would not say what exactly led to charging Zimmerman.

Update at 6:06 p.m. ET: Zimmerman is in custody but Corey would not reveal his whereabouts "for his safety."

Update at 6:02 p.m. ET: George Zimmerman is being charged with second-degree murder for the Feb. 26 shooting death of 17-year-old Trayvon Martin, which the neighborhood watch volunteer has claimed was in self-defense, the special prosecutor, Florida State Attorney Angela Corey, has announced.

Corey said she had spoken with Trayvon's parents shortly before appearing at the state attorney's office in Jacksonville.

She said that she "did not come to this decision lightly" and that "we do not prosecute by public pressure."

Update at 5:53 p.m. ET: Sanford Mayor Jeff Triplett and City Manager Norton Bonaparte Jr. will hold a news conference after Corey's announcement.

Update at 5:43 p.m. ET: George Zimmerman is be charged with second-degree murder, a law enforcement official tells AP.

CNN is reporting that he is in custody.

Update at 4:18 p.m. ET: The law enforcement official who spoke to AP said that Zimmerman is not in Florida but that authorities know where he is. They are planning to arrest him soon rather than let him surrender.

At their news conference Tuesday, defense attorneys Hal Uhrig and Craig Sonner said that they did not know Zimmerman's whereabouts but that he was in the United States and had not fled the country.

They also said that although they had been in daily contact with him by phone, email and text messages, they had not met him personally.

Update at 3:37 p.m. ET: Before special prosecutor Angela Corey announced her news conference, U.S. Attorney General Eric Holder pledged that a federal civil rights inquiry into Trayvon's death would be "a thorough and independent review of the evidence,'' USA TODAY's Kevin Johnson says.

"Although I cannot share where current efforts will lead us from here,'' Holder said in a speech to the National Action Network, a civil rights group that has been calling for an arrest in the case, "I can assure you that, in this investigation — and in all cases — we will examine the facts and the law. If we find evidence of a potential federal criminal civil rights crime, we will take appropriate action. And at every step, the facts and the law will guide us forward.

"I also can make you another promise: that at every level of today's Justice Department — preventing and combating youth violence and victimization is, and will continue to be, a top priority," Holder said, calling Trayvon "a young man whose future has been lost to the ages."

The Justice Department launched an investigation of the killing three weeks ago.

Original post by Douglas Stanglin:

Update at 3:08 p.m. ET: Trayvon Martin's parents, in Washington to attend the National Action Network convention, say they are "confident'' in the criminal justice system and are appealing for a peaceful reaction to whatever decision is announced by the Florida special prosecutor, USA TODAY's Kevin Johnson reports.

"It's been a nightmare for 44 days,'' says Sybrina Fulton, the slain teenager's mother, referring to the time since her son was killed. "God is holding me up and keeping me. … I know beyond a shadow of a doubt that justice will be served.''

Rev. Al Sharpton, president and founder of NAN, which has been leading a series of protests in wake of Trayvon's death, is calling for calm in anticipation of the prosecutor's decision.

"Trayvon Martin's name must not be tarnished,'' Sharpton says. "We denounce anything other than non-violence. We are not in the business of revenge. We are in the business of justice.''

Update at 2:38 p.m. ET: The Associated Press quotes a law enforcement official as saying that charges will filed in the Trayvon Martin shooting case and that an announcement will be made at 6 p.m. ET today.

Update at 2:34 p.m. ET: CNN reports that Corey will hold a news conference within the next four hours to release information on the case.

Update at 2:23 p.m. ET: NBC News reports that criminal charges will be filed against Zimmerman.