A laptop computer seized from the vehicle of a man accused of killing three people in western Idaho could unveil clues into a motive for the shooting rampage, authorities say.

Police allege John Lee, 29, opened fire at three locations Saturday afternoon in Moscow, Idaho, killing his adoptive mother, his landlord and then a manager at a restaurant his parents frequented. A Seattle man was critically injured.

Lee was arrested following a high-speed chase in nearby Washington state in the hours after the shootings.

Investigators searched his car, recovering two semi-automatic pistols, a revolver, a shotgun and a rifle, along with the laptop, Moscow Police Chief David Duke said. Ballistics tests were expected to help determine which weapons might have been used in the rampage.

"We have a high confidence we do have the weapon," Duke said Monday morning.

Earlier, he said authorities were seeking a warrant to search the computer.

"There's still nothing to identify a specific motive as to why Mr. Lee took these actions," Duke said.

Lee's adoptive mother, Terri Grzebielski, 61, was killed first, at her home. Police said Lee then headed to Northwest Mutual life insurance, where he shot his landlord, David Trail, 76, who was a local businessman and the brother of a former state representative, as well as Michael Chin, 39, of Seattle.

Chin had no link to Lee, but he was discussing business with Trail when the gunman arrived, Duke said. Chin was shot in the arm and leg and flown in critical condition to a hospital in Washington state, authorities said.

Duke said Monday that Chin had been moved Sunday night from the intensive-care unit to a regular room.

"With him moving out of ICU, we feel that his condition has improved," the police chief said.

There were "some issues" regarding Lee's apartment, Duke said, but no eviction proceedings known to police.

Upon leaving the insurance office, the shooter drove to an Arby's restaurant and asked for the manager. When she appeared, he pulled out a gun and opened fire. The manager, Belinda Niebuhr, 47, died at a hospital.

Lee's parents ate at the restaurant and knew the manager well, but it's not clear whether their son did, too, Duke said. He did not work at the restaurant as far as police knew, and workers who witnessed the attack didn't recognize him, the chief said.

Kelsey Stemrich said she was working at a cafe near Arby's when she and a customer heard three gunshots and then saw people running from the restaurant. She says they took down the license-plate number of a car seen pulling away and called police.

Police in Washington spotted the suspect's black Honda, and a chase involving multiple agencies ensued. Pullman Police Chief Gary Jenkins said the pursuit lasted nearly 25 miles, and Lee's vehicle at times topped 100 mph before crashing off a highway north of Colfax, a small town in eastern Washington, and rolling to a stop.

Duke said Monday that Lee pulled into oncoming traffic to make a pass but started fishtailing and lost control, flipping end over end two or three times.

Lee was taken to a hospital in Colfax for treatment of minor injuries before he was booked into jail on a charge of felony eluding. Idaho authorities issued an arrest warrant for Lee on suspicion of three counts of first-degree murder and one count of attempted murder, Duke said, and they could take Lee into custody from Washington state by Monday unless he fights extradition.

Duke said Lee had been adopted at birth, and he recently returned to Moscow after living for a few years in the Midwest. Few other details on his background were available, and police were working to fill in those gaps. Duke also said police were looking for possible video from the sites of the shootings.

Moscow, a city of about 25,000 people in northern Idaho, was the site of another shooting rampage, in 2007. A gunman in the city about 10 miles from Pullman, Washington, killed a Moscow police officer and a church caretaker before shooting himself. A sheriff's deputy and a resident were also wounded in the attack.

"We're familiar with these types of cases," Duke said.