Investigators are probing the background of a suspect in a shooting spree in Moscow, Idaho, that left three people dead and another critically wounded.

A gunman opened fire Saturday at three separate locations in the western Idaho city, killing a victim at each site.

John Lee, 29, the suspected attacker, was captured in the afternoon following a high-speed chase in nearby Washington state.

Moscow Police Chief David Duke said Lee killed his adoptive mother, 61-year-Terri Grzebielski, at her home before heading to Northwest Mutual life insurance.

The gunman shot David Trail, 76, a Moscow businessman, and Michael Chin, 39, of Seattle. Trail died at Pullman Regional Hospital. Chin was treated for critical wounds at Gritman Medical Center in Moscow before being flown to a Seattle hospital, Duke said.

The shooter then drove to an Arby’s restaurant and asked for the manager. When she appeared, he pulled out a gun and opened fire. The manager, 47-year-old Belinda Niebuhr, died at the Moscow hospital.

Duke said that Trail, the brother of a former Idaho state representative, was Lee’s landlord. He said there were "some issues" regarding the apartment, but didn’t know of any eviction proceeding.

He said Chin had no link to Lee but was discussing business with Trail when the gunman arrived. Duke said Chin was shot in the arm and leg.

Investigators were trying to determine if there were any links between Lee and the Arby’s manager.

"We know he didn’t work there," Duke said. The chief said that the surviving workers did not recognize Lee.

Duke told The Associated Press later that police have determined that Lee’s parents ate at the restaurant and knew the manager well.

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 from the Arby’s and called it into police.

Few details were available Saturday on Lee’s background. Duke said that he had been adopted at birth and he recently returned to Moscow after living for a few years in the Midwest.

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 Highway 195 north of Colfax and rolling to a stop.

Lee was taken to a Colfax hospital for treatment of minor injuries before he was booked into the Whitman County Jail on a charge of felony eluding. Investigators had yet to recover the gun. Duke said it was probably still in the car and detectives were awaiting a search warrant Saturday night before looking for it.

Moscow authorities had yet to announce any Idaho charges late Saturday, saying the investigation remains active.

Moscow is a city of about 25,000 people in northern Idaho. It’s about 10 miles from Pullman, Washington.

Associated Press writer Phuong Le contributed to this report.