SEATTLE -- Police described a suspect in the shooting death of a Seattle policeman as a "lone domestic terrorist" and said he was also suspected of firebombing four police vehicles.

At a news conference, Seattle Assistant Police Chief Jim Pugel identified 41-year-old Christopher Monfort as the man shot by police on Friday as he was sought in connection with the Halloween killing of officer Timothy Brenton. Pugel also said investigators found improvised explosive devices at Monfort's apartment.

"This man, from everything we can tell is a lone domestic terrorist," Pugel said. "At this moment we cannot find any ties to anyone else."

Police evacuated part of Monfort's apartment complex Saturday evening after finding what was described as a "potential hazard," Seattle's KING 5 News reported. Police didn't elaborate on the evacuation but allowed residents to return to their homes after about an hour.

Brenton was sitting in a car Oct. 31 with rookie Officer Britt Sweeney following a traffic stop when shots were fired. Sweeney was grazed in the neck.

Detectives have asked the King County prosecutor's office for formal charges in the case.

On Sunday morning, Monfort was still in serious condition in the intensive care unit at Harborview Medical Center, said hospital spokeswoman Susan Gregg-Hanson. He underwent hours of surgery Friday night and arrived at the hospital in critical condition with "multiple injuries."

Pugel said police believe Monfort is connected to the Oct. 22 firebombings of three Seattle police cruisers and a mobile command post at a nearby city garage. Investigators reportedly found a note threatening to kill officers and fliers protesting police brutality at the arson scene.

The Seattle Times reported that an American flag found at the maintenance yard and a similar one found near the shooting scene gave investigators a key link between the two crimes even before Monfort was identified as the suspect. The Times attributed the information to unnamed law-enforcement sources.

On Friday, police detectives were pursuing a tip from the resident who said a car at an apartment complex in suburban Tukwila matched the description of a vehicle seen nearby when Brenton was killed.

While officers examined the car, which was covered by a tarp, television footage showed dozens of cruisers surrounding the building.

Pugel said detectives were walking to speak with other law enforcement conducting surveillance when Monfort left his apartment and approached the three detectives.

According to Pugel, detectives started asking Monfort questions at which time he pulled a gun and tried to shoot. Monfort tried to escape up a set of stairs after the gun failed to go off, Pugel said.

At the top of the stairs, Pugel said, Monfort again displayed his gun toward detectives who fired shots. The detectives fired four to six times, although Pugel did not know how many times Monfort was hit.

Pugel said the three Seattle police detectives who shot Monfort have been placed on administrative leave, which is routine after an officer-involved shooting.

Friday's shooting happened as a memorial service for Brenton was finishing at Seattle's KeyArena.

Inside Monfort's apartment, Pugel said, investigators found two rifles in the apartment, including a military-style assault rifle being examined as the possible weapon used to kill Brenton.

Pugel also said police disarmed the improvised explosive devices found in the apartment before removing them.

Monfort received a bachelor's degree from the University of Washington in March 2008, according to the university's degree-validation Web site. His major was in Law, Societies and Justice.