Richard Rojas, 26, a US Navy veteran who was arrested twice previously for drink-driving, is now in custody.
He also said he expected to die, the sources told AP news agency.
According to Reuters, he said after being arrested: "You were supposed to shoot me! I wanted to kill them."
Mr Rojas has been charged with murder in the second-degree, 20 counts of attempted murder, and five counts of aggravated vehicular homicide. He is expected to appear in court later on Friday.
