SANFORD, Fla. -

George Zimmerman has been arrested and is being charged with second-degree murder for the fatal shooting of Trayvon Martin on Feb. 26. 

Special prosecutor Angela Corey announced the charge at a news conference Wednesday, seven weeks after the homicide took place. 

Trayvon Martin's parents, civil rights leaders and other people have portrayed the case as racially charged, saying Zimmerman would have been arrested immediately had he been black and the victim white. Martin was black. 

The case has raised a multitude of questions, some of which remain unanswered. 

Q: WHY DID IT TAKE SO LONG FOR ZIMMERMAN TO BE ARRESTED? 

A: Special prosecutor Angela Corey says that probable cause had to be determined before authorities could arrest Zimmerman. She said there was only a slight delay, when she took it over from the previous prosecutor, who recused himself from the case. 

Zimmerman told police he acted in self-defense after Martin pursued and attacked him. Florida is among 21 states with a "stand your ground law," which gives people wide latitude to use deadly force rather than retreat during a fight. The Florida law lets police on the scene decide whether they believe the self-defense claim. 

In many cases, the officers make an arrest and leave it to the courts to work out whether the deadly force is justified. In this case, however, police have said they are confident they did the right thing by not charging Zimmerman. 

Q: ON WHAT EVIDENCE IS THE PROSECUTOR BASING THE CHARGE OF SECOND-DEGREE MURDER? 

A: Corey did not disclose how she arrived at the charge, saying that was information to be revealed in court. 

Q: WHAT'S NEXT? 

A: Zimmerman will appear in court within 24 hours, Corey said. 

Q: DOES ZIMMERMAN HAVE LEGAL COUNSEL? 

A: Yes, Mark O'Mara of Orlando, who became Zimmerman's new attorney after his former lawyers announced Tuesday that they were dropping the case. They said they couldn't keep representing Zimmerman because he had stopped communicating with them. 

Q: WHAT HAPPENED? 

A: Martin, 17, was shot and killed by a single gunshot wound to the chest Feb. 26 during a confrontation with Zimmerman, a 28-year-old neighborhood watch volunteer in a gated community of townhomes in Sanford, Fla., about 20 miles northeast of Orlando. 

Zimmerman was driving through the neighborhood when he spotted Martin, who was unarmed and walking to the home of his father's fiancee. She lived in the same gated community as Zimmerman. 

Martin was returning from a trip to the convenience store with an iced tea and a bag of Skittles. It was raining, and Martin was walking with the hood of his sweatshirt pulled over his head. He talked to his girlfriend on a cellphone moments before the shooting, according to Martin's family's attorney. 

Q: WHAT IS GEORGE ZIMMERMAN'S SIDE OF THE STORY? 

A: On his website, therealgeorgezimmerman.com, Zimmerman has described the shooting as "a life altering event" but he says he can't go into details about what happened. 

"As a result of the incident and subsequent media coverage, I have been forced to leave my home, my school, my employer, my family and ultimately, my entire life," he said on the site. 

Zimmerman has told police that he spotted Martin as he was driving through his neighborhood and called 911 to report a suspicious person. 

"This guy looks like he is up to no good. He is on drugs or something," Zimmerman told the dispatcher from his truck. He added that the teen had his hand in his waistband and was walking around looking at homes. 

"These a-------. They always get away," Zimmerman said on a 911 call. 

There had been several break-ins in the community in the past year, including one in which burglars took a TV and laptops. 

A dispatcher told Zimmerman he didn't need to follow Martin after Zimmerman got out of his truck and started following the teen. 

Zimmerman told police he lost sight of the teenager and was walking back to his vehicle when he was attacked. He and Martin fought, according to witnesses. Zimmerman said Martin punched him in the nose and slammed his head against the ground. 

At some point, Zimmerman pulled a gun and shot Martin. Zimmerman told police he acted in self-defense. 

Police said Zimmerman was bleeding from his nose and the back of his head. He told police he had yelled out for help before he shot Martin. 

He has not been arrested or charged, but a law enforcement official told The Associated Press on Wednesday that the special prosecutor in the case plans to arrest and charge him. The prosecutor has announced a news conference for 6 p.m. Wednesday, but hasn't said what information she will release. 

Q: WHAT IS THE MARTIN FAMILY'S SIDE OF THE STORY? 

A: Much of Martin's side of the story comes from a cellphone conversation he had with his girlfriend moments before the shooting. She was interviewed by the family's attorney, Benjamin Crump, and he released much of what she said to the news media. She has not been identified. 

In the interview, she said Trayvon Martin told her that he was being followed. 

"She says: `Run.' He says, `I'm not going to run, I'm just going to walk fast,"' Crump said, quoting the girl. 

The girl later heard Martin say, "Why are you following me?" Another man asked, "What are you doing around here?" Crump said. 

After Martin encountered Zimmerman, the girl thinks she heard a scuffle "because his voice changes like something interrupted his speech," Crump said. The phone call ended before the girl heard any gunshots. 

Martin's parents said their son made the pleas for help that witnesses heard. 

Q: WHAT IS GEORGE ZIMMERMAN'S RACIAL AND ETHNIC BACKGROUND? 

A: Zimmerman's father is white, and his mother is Hispanic of Peruvian descent. 

Q: WHERE IS GEORGE ZIMMERMAN? 

A: Zimmerman is in the custody of law-enforcement officials in Florida, Corey said. She said he turned himself in.