The gunman behind Thursday’s massacre in Umpqua Community College, who killed nine people and injured at least seven others before killing himself left behind a letter in which he wrote his grievances, a law enforcement official told US media.
The 26-year-old gunman Christopher Harper-Mercer complained in the document about not having a girlfriend, he also proceeded to call everyone “crazy,” and added that he was the only sane person.
The official who wasn’t authorized to speak publicly, due to the ongoing investigation, also said that Harper-Mercer's mother told police that he had been suffering from various mental problems.
Previously, survivors had claimed the shooter left behind a message.
The mother of one of the survivors told US media that Mercer handed her son an envelope and told him to give it to the police.
Mercer killed eight students as well as a teacher and injured at least seven people at Umpqua Community College in the state of Oregon in the US, where he was also a student.
On Monday, students were welcomed back to campus at the community college by faculty and staff, for the first time since the shooting, but classes will not resume until next week.
Meanwhile, a White House official said that US President Barack Obama will visit Roseburg, Oregon on Friday to meet families of victims. Obama again called for stricter gun control laws in the US, following the shooting.
Only in 2015, 364 were killed and 1,082 injured in mass shootings in the United States.