TACOMA, Wash. — The suspect in the execution-style killing of four Tacoma-area police officers, Maurice Clemmons, continued to evade police throughout Monday with police officers following tips on his whereabouts in Seattle and Pierce County after a stakeout of a Seattle house failed to capture the suspect.

The most valuable tips are in Seattle, Puyallup police Lt. Dave McDonald said during a briefing. "We don't believe he's in the Parkland area" -- the town where the four officers from the Lakewood Police Department were gunned down.

McDonald said investigators believe Clemmons, who they believe was shot in the torso by one of the dead officers, is getting help.

"It's apparent people are helping him," McDonald said. "Anyone helping him ... will be held accountable."

He added that not finding Clemmons in the house on Yessler Way in Seattle early today was extremely frustrating for officers.

"We expect to follow all the leads," McDonald said. "It's a true manhant."

Investigators did find a gun inside the coffee shop where the four officers were doing paperwork when they were killed.

McDonald said the key to the investigation was the light-colored pickup truck spotted by a witness right after the shooting. The witness reported that Clemmons got into the truck.

An alert Pierce County deputy quickly found the truck abandoned at a grocery store parking lot in Parkland. The truck was registered to Clemmons, McDonald said.

At the crime scene, the investigation and land search continues. The Pierce County sheriff's dive team was searching a pond at a nearby apartment complex for any possible evidence.

McDonald added that he knew Sgt. Mark Renninger, one of the slain officers. He said all Pierce County officers are in shock over the slayings.

"We are trying to stay busy," McDonald said.

Five Pierce County sheriff's deputies planted a small American flag amid the piles of flowers at the Parkland memorial scene.

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