SEATTLE, Washington (CNN) -- The suspect in the fatal shooting of four police officers was shot and killed early Tuesday in south Seattle after he challenged police who approached him, authorities said.
The Seattle Police Department confirmed to the Pierce County Sheriff's Department that an officer killed Maurice Clemmons, sheriff's spokesman Ed Troyer said.
"They came in contact with the suspect about an hour ago," Troyer said shortly before 4 a.m. PT (7 a.m. ET). "When they came in contact, shots were fired. The suspect was shot and killed."
The shooting took place in the 400 block of South Kenyon Street.
It ended a two-day manhunt for Clemmons, 37, that began Sunday after an ambush-style killing of four police officers from Lakewood, about 40 miles south of Seattle.
Troyer could not immediately say whether Clemmons was armed or whether he exchanged gunfire with police. Troyer was headed to the scene and said authorities will have more information in a news conference set for later in the morning.
"The Seattle Police Department is the agency that shot and killed him after the incident occurred," he said. "We had supplied information to them earlier on multiple occasions where the suspect could possibly be at, along with a bunch of other police agencies that were running multiple operations. And at this point we do have the suspect. He's no longer out there."
Monday night, investigators had rounded up several of Clemmons' relatives and friends to keep them from helping him elude police.
Some of Clemmons' family and friends had tried to help him seek treatment for a gunshot wound that he suffered during the Sunday attack. They also called in false leads to police to divert investigators, Troyer said.
Clemmons was an ex-convict with a long rap sheet in Washington and Arkansas, according to authorities and documents.
Witnesses say Clemmons was shot in the torso during the Sunday morning attack, and blood and gauze bandages were found in a truck linked to Clemmons, Troyer said.
Clemmons is thought to have 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 the investigators moved in Monday morning, Seattle police spokesman Jeff Kappel told reporters.
His escape was "an unlucky thing for us, and a lucky thing for him," Troyer said Monday night. "But his luck's going to run out, because he doesn't have people to help him do that any more."
The slain officers -- three men and a woman -- were killed at a coffee shop in Parkland, a suburb of Tacoma. Early Monday, authorities started identifying Clemmons as a suspect, rather than as someone wanted for questioning.
The night before the shootings, Clemmons had threatened to kill police officers, but witnesses did not report those threats until after the slayings, Troyer said on "Good Morning America."
Clemmons was accused of child rape and assaulting a police officer in May, and had been released on $150,000 bond 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.
"Should he be found responsible for this horrible tragedy, it will be the result of a series of failures in the criminal justice system in both Arkansas and Washington state," Huckabee's office said in a statement Sunday night.
During his 2008 presidential bid, Huckabee was criticized for granting clemency to another inmate, convicted rapist Wayne DuMond, who was later convicted of raping and murdering a woman in Missouri. Huckabee's statement brought a sharp response from Troyer on Monday.
"We're disappointed that Governor Huckabee came out in the middle of the night without calling anybody here and blamed this on the criminal justice system in the state of Washington," Troyer said. "We're guessing that's probably a spin doctor, not him."
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 there.
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."
Lakewood Police Chief Bret Farrar told reporters Monday that he has repeatedly been asked how the city's officers are doing.
"This is how everybody's doing," Farrar said, gesturing to the police force standing behind him. "They're here. They're doing their jobs. They're working hard. They're dealing with their loss. ... We're here to carry on. This is what we do."
The four officers "were good people," Farrar said, fighting to maintain his composure. "They were great officers, and we will all miss them very much."
The Lakewood Independent Police Guild is accepting donations for the officers' families, said guild president and Lakewood police officer Brian Wurts. Contributions have poured in from as far away as Switzerland, he said.
"I can't believe he was out on the street," Wurts said of the suspect.
"If they want to rehabilitate them, you can rehabilitate them -- but you rehabilitate them in prison, where they're supposed to be," he added. "This guy should have never been on the street."
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 Company 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. PT Sunday. 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. All were in uniform, with their marked patrol cars parked outside. Two baristas and other customers inside the shop were unharmed.
"Just the law enforcement officers were targeted," Troyer said.