Seattle, Washington (CNN) -- The suspect in Sunday's fatal shooting of four police officers was shot and killed early Tuesday in south Seattle after he challenged an officer who approached him, authorities said.
Maurice Clemmons was carrying a weapon taken from one of the dead officers and had suffered a bullet wound to his abdomen in Sunday's shooting, Pierce County Sheriff's Department spokesman Ed Troyer said at an early morning news conference.
Clemmons was killed around 2:45 a.m. by a seven-year veteran of the Seattle police force who had noticed a parked stolen car that was unoccupied but running, said Jim Pugil, an assistant Seattle police chief.
The officer approached Clemmons outside the car and asked him to show his hands, but the suspect refused and started to run around the car, Pugil said.
The police officer, who recognized Clemmons from photographs, then shot and killed him, the assistant chief said.
The officer, who was not identified, was not injured.
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Authorities said they regretted the shooting death but are glad the two-day ordeal is over.
"Right now, it's just a feeling of relief," Pugil said. "Another tragic time has come upon us, and we're just happy that it's over."
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* Mike Huckabee
Seattle police Chief John Diaz said, "This is a tragedy. Nobody feels good about this."
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"I am thankful the suspect in this horrible crime is no longer a threat to our community," Washington Gov. Christine Gregoire said in a statement. "I hope this provides some closure for the families and colleagues of our fallen officers ... We should now focus our attention on providing comfort and support to those who have lost a loved one."
Authorities have arrested at least three people on suspicion of aiding Clemmons after the shooting, Troyer said. Police also arrested a man Tuesday morning suspected of driving the getaway car after Sunday's killings, Troyer said.
The people accused of trying to help Clemmons provided medical aid, housing, a cell phone and money and were trying to get him out of the state, Troyer said. They also called in false leads to police to divert investigators, Troyer said.
"They're going to pay for it," he said. "They're guests of ours."
Troyer did not identify the suspects but said authorities expected to make more arrests Tuesday.
Clemmons had made comments before the shooting that he was going to kill some officers -- comments that were not reported to authorities until after the shootings -- but officials believe he was the lone gunman.
"We don't think anyone helped him plan this murder," Troyer said.
A two-day manhunt for Clemmons, 37, began Sunday after the ambush-style killing of four police officers from Lakewood, about 40 miles south of Seattle. The officers were at a local coffee shop when Clemmons walked in and shot them, police say.
Clemmons was an ex-convict with a long rap sheet in Washington and Arkansas, according to authorities and documents.
Watch a profile of Clemmons
Clemmons slipped away from a home in Seattle's Leschi neighborhood Sunday night before police surrounded the residence for about 12 hours. He was not found in the home when investigators moved in Monday morning, Seattle police spokesman Jeff Kappel said.
Officials said Tuesday they missed him by mere minutes.
Clemmons was accused of child rape and assaulting a police officer in May. He had been released on $150,000 bail five days before the shootings, according to court records.
After his arrest, Clemmons' sister told police that he "had not been himself lately" and that his behavior was "unpredictable and erratic."
"He had said that the Secret Service was coming to get him because he had written a letter to the president," an affidavit quoted her as telling investigators.
In addition, neighbors had complained that he had been throwing rocks through their windows. Clemmons' wife told deputies that she and her husband had argued over a "newly discovered child," and she suggested that was why he went on his rock-throwing spree, according to an arrest affidavit.
In 2000, then-Arkansas Gov. Mike Huckabee commuted a 95-year prison sentence for Clemmons, according to documents from the Arkansas Department of Community Correction. He returned to prison in 2001 but was paroled in 2004.
Sunday's shooting was the first for the Lakewood Police Department, which was created five years ago for the town of nearly 60,000. Until then, the Pierce County Sheriff's Department provided law enforcement services.
The slain officers were identified as Sgt. Mark Renninger, 39; Officer Ronald Owens, 37; Officer Tina Griswold, 40; and Officer Greg Richards, 42. All of them were parents and had been with the department since its inception.
"My worst nightmare has come true," Tiffany Ryan, Griswold's sister, told reporters. "I can't tell you how painful it is to lose my sister."
The coffee shop on Steele Street where the shootings occurred is a popular hangout for law enforcement officers and is one of 22 Forza Coffee Co. locations in Washington.
Police said the gunman walked past the officers to the counter as if to order, then pulled a gun out of his coat and began shooting at 8:15 a.m. Two of the officers were "executed" as they sat at a table, Troyer said.
Another was shot when he stood up, and the fourth was shot after struggling with the gunman all the way out the door, Troyer said.
Clemmons suffered a gunshot wound to the abdomen. Officials said Tuesday they know which officer shot him but were withholding that information pending conclusive confirmation. The wound was serious, Troyer said.
"I'm surprised he survived it," Troyer said. "He was lucky."