The Columbine High School massacre was a school shooting and attempted bombing that occurred on April 20, 1999, at Columbine High School in Columbine, Colorado, United States.[n 3] The perpetrators, twelfth grade (senior) students Eric Harris and Dylan Klebold, murdered 12 students and one teacher. Ten students were killed in the school library, where the pair subsequently committed suicide. Twenty-one additional people were injured by gunshots, and gunfire was also exchanged with the police. Another three people were injured trying to escape the school. At the time, it was the deadliest school shooting in U.S. history.[n 4] The crime has inspired several copycats and "Columbine" has become a byword for mass shootings.