A Florida prosecutor filed a murder charge on Wednesday against the neighborhood watch volunteer who shot and killed unarmed black teenager Trayvon Martin in a case that has captivated the United States and prompted civil rights demonstrations.


George Zimmerman, 28, was arrested and charged with second-degree murder in the death of 17-year-old Martin, according to Angela Corey, the special prosecutor appointed by Florida's governor to investigate the racially charged case.


Corey announced the latest developments in the case at a news conference in Sanford, Florida, the town where Martin was killed more than a month ago.


"We will continue to fight for justice for Trayvon, not only for our family but to help prevent racial profiling from happening to other teens," said Trayvon's father, Tracy Martin. "Our family thanks all of the people who helped share Trayvon's story by signing our petition."


More than 2.2 million people signed a petition on Change.org asking for an investigation on Trayvon's killing.


"I'm a normal mother. I just want justice for my son," said Trayvon's mother, Sybrina Fulton, about her campaign on Change.org. "It has been so powerful to see so many people stand with our family by signing this petition and we feel much closer to justice with the decision to bring charges against our son's killer. We are thankful to the millions of people around the world who signed the petition on Change.org and called for justice for Trayvon."