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Trayvon Martin timeline: Key events in the Sanford, Fla., shooting case

Mary Altaffer / AP

Demonstrators pray during the Million Hoodie March in Union Square Wednesday, March 21, 2012 in New York. The march was in memory of Trayvon Martin, an unarmed teen shot and killed in Florida in February.

Feb. 26, 2012: Fatal Shooting
Trayvon Martin, 17, is shot and killed while walking through a Sanford, Fla., community where he is visiting family. Neighbors call police to report hearing a scuffle and a gunshot. Martin is found dead by police. George Zimmerman, neighborhood watch captain, is taken to the Sanford Police Department for questioning about the shooting, which he says was in self-defense. No charges are filed and he is not arrested.

March 16: 911 tapes released
Martin’s parents gain access to 911 calls made to police on the evening of the shooting and portions of those tapes are made public. One recording indicates that Zimmerman says he is following Martin and a dispatcher tells him that's not necessary. In another, there are audible cries for help in the background. Martin's family demands an arrest and petitions calling for the same gain tens of thousands of signatures within a matter of hours.

March 19: Investigation launched
The U.S. Justice Department announces it has launched an investigation into the shooting.

March 21: Million hoodie march
Martin’s parents join hundreds of protesters in New York City demanding justice in what is dubbed the "Million Hoodie March," a tribute to Martin, who was wearing a hooded sweatshirt at the time of his death. It is the first of what will become large protests across the country.

March 22: Police chief steps aside
Sanford Police Chief Bill Lee announces he will step down "temporarily" amid accusations that he has mishandled the Martin case and after a vote of no confidence by city commissioners. Thousands of people join a rally in Sanford organized by the Rev. Al Sharpton demanding Zimmerman’s arrest. (Sharpton is a civil rights activist and also a host on the msnbc cable television show Politics Nation.)

March 23: White House mention
President Barack Obama raises the Martin case at the end of a White House press conference in which he names Jim Yong Kim as his nominee for the World Bank president. In response to a reporter's question about the case, Obama says: "If I had a son, he would look like Trayvon."

March 24: Threats against Zimmerman
At a protest in Florida, leader of the New Black Panther Party Mikhail Muhammad announces a $10,000 bounty for the capture of Zimmerman, who is in hiding.

April 10: Lawyers quit
Craig Sonner and Hal Uhrig, lawyers for Zimmerman, announce they will no longer represent him because he has stopped communicating with them.

April 11: Charges pending
Florida special prosecutor Angela Corey announced that she will pursue a second-degree murder charge in Trayvon Martin's killing. Zimmerman turned himself in to police.

April 20: Zimmerman apologizes
At the bail hearing, Zimmerman spoke to Martin's parents: “I wanted to say I am sorry for the loss of your son." Following the hearing, Natalie Jackson, an attorney for the Martin family, said Zimmerman's apology was "insulting to the family."

April 23: Zimmerman released
Zimmerman is released on $150,000 bail. Circuit Judge Kenneth Lester says Zimmerman cannot have any guns and must observe a 7 p.m.-to-6 a.m. curfew. Zimmerman surrenders his passport and puts on an ankle bracelet.

April 30: Lawyer asks for help
Mark O'Mara, Zimmerman's lawyer, launches an all-out social media blitz to tell Zimmerman's side of the story. The web site also asks for donations.

May 14: State files witness list
Special prosecutor Angela Corey files the witness list and evidence that will be presented, including video from the night of the shooting, crime scene photographs and 56 audio-recorded statements.

May 15: Martin shot at 'intermediate range'
An autopsy shows that in addition to the gunshot wound, Martin also incurred a small abrasion under his left knuckle. Separately, a physician's report from the day after the shooting indicated that Zimmerman had “a pair of black eyes, two lacerations to the back of his head and a minor back injury.”

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