The man allegedly behind the deadly shooting rampage in northern Idaho this weekend had five guns and a laptop computer stashed in his car, investigators said Sunday. John Lee, 29, is suspected of killing three people and critically wounding a fourth in the city of Moscow.

Lee was arrested late Saturday after he crashed his car during a high-speed police chase. Earlier in the evening, he allegedly shot and killed his mother at her home, then drove to his landlord's office and opened fire, killing the landlord and critically wounding a bystander, police said. Lee continued on to a nearby Arby's restaurant where he asked to see the manager then allegedly shot and killed the 47-year-old woman.

Investigators later searched Lee's black Honda Fit and found a laptop plus two semi-automatic pistols, a revolver, a shotgun and a rifle, the Associated Press quoted Moscow Police Chief David Duke as saying. Police performed ballistics tests to figure out which weapons were used in the shootings.

So far, however, "there's still nothing to identify a specific motive as to why Mr. Lee took these actions," Duke told the AP. He said Lee's parents frequented the Arby's restaurant and knew the manager well, but it's unclear if Lee did too. Duke said authorities would likely search the laptop found in Lee's car for further clues, Reuters reported.

"The city and community are grieving at this point, but it’s a strong community," Duke said.

Moscow is a city of about 25,000 and sits about 10 miles from Pullman, Washington. Lee fled to Pullman during the police chase and crashed his car on the Washington side of the border. Washington police detained and jailed him on a charge of felony eluding. Lee is currently awaiting extradition to Idaho where he faces first-degree murder and attempted murder charges, media reports indicate.

Duke told the AP Idaho authorities could take Lee into custody from Washington by Monday unless he fights extradition.