Oregon gunman ranted about not having girlfriend, others being 'crazy'; Obama to visit Roseburg Friday

ROSEBURG, Ore. -- The gunman who killed nine people in an Oregon classroom last week ranted about not having a girlfriend in a manifesto and said he was sane while others were "crazy," a law enforcement official said Monday.

The official is familiar with the investigation but commented on condition of anonymity. The official says that in the multi-page document left behind for authorities last week, Christopher Harper-Mercer also complained that others around him thought he was crazy.

The official says the gunman wrote he was sane and others were unbalanced.

Harper-Mercer opened fire at Umpqua Community College in Roseburg, killing nine. He committed suicide as officers arrived on the scene. Another nine people were wounded.

Also on Monday, it was announced that President Barack Obama will travel to Oregon Friday to visit privately with families of the victims of the shooting.

Obama will visit Roseburg on Friday as he opens a four-day trip to the West Coast. No additional details about his visit were immediately available.

Obama has renewed his call for stricter gun laws following the shooting and has expressed exasperation at the frequency of mass shootings in the U.S.