Trayvon Martin, 17, was killed in February by a 28-year-old man, George Zimmerman, who claimed to be a part of the neighborhood watch in a Florida gated community. The case is currently under investigation by federal and local authorities after a flood of media attention called for the arrest of Zimmerman.

Derrion Albert, 16, was caught in a fight between two groups in 2009. He was brutally beaten by several young men. The incident led to national focus on violence in Chicago. The people tried in Albert’s death received sentences from seven to 27 years in prison.

Oscar Grant, III, 23, was pulled out of a San Francisco-area BART train by police on New Year’s Day. Several videos show Grant laying on the ground with police standing over him. One officer shot him in the back. The officer was found guilty of second degree manslaughter and sentenced to two years, minus time served.

Sean Bell, 23, was killed by the NYPD in 2006. Officers said they believed Bell and friends were armed when they began shooting into their car. The officers involved were acquitted on all charges.

Amadou Diallo, 23, was a Guinean immigrant in who was shot and killed on February 4, 1999 by four New York City Police Department plain-clothed officers. Officers said they believed he had a gun when he reached for his wallet.

Yusuf Hawkins, 16, was fatally shot in the Bensonhurst neighborhood of Brooklyn, New York by a white mob in the summer of 1989. Hawkins and friends were chased and beaten with baseball bats by a mob of 10-30 white teens.

Michael Griffith, 23, was with friends on December 19, 1986 when their car broke down near the Howard Beach section of New York. They went to a local pizzeria to call for help and were confronted by a group of more than 10 white teens. A fight ensured that led Griffith to run into the street nearby, where he was hit by a car and killed.

Michael Donald, 20, is often referred to as the last man lynched in the United States. In 1981, his badly beaten body was found hanging from a tree in Mobile, Alabama with his throat slit. The FBI conducted an investigation that led to the arrest and conviction of two Klan members responsible for the murder.

14-year-old girls Addie Mae Collins, Cynthia Wesley, Carole Robertson and Denise McNair (11,) were killed in the bombing of Birmingham’s 16th Street Baptist Church in 1963. The case was unsolved until 1977 when a 77-year-old man, Robert Chambliss, was found guilty and sentenced to life imprisonment.

Emmett Till, 14, was murdered in the summer of 1955 in Mississippi, while visiting relatives. Tens of thousands of people attended his funeral in Chicago. The murder galvanized black Americans and motivated the Civil Rights Movement.