PARKLAND, Wash. - A gunman walked into a coffee shop and shot and killed four police officers Sunday morning in what sheriff's officials described as an "execution."

The officers were sitting in the cafe at a strip mall near the Tacoma suburb of Parkland with their laptop computers, preparing for their day shifts, when a man came in and opened fire, Pierce County Sheriff's spokesman Ed Troyer said.

The officers were obviously targeted because they were in full uniform and no one else was shot at, Troyer said.

"This was more of an execution. He walked in with the mind of shooting police officers," Troyer said.

It wasn't immediately known if any of the officers were able to return fire. They were declared dead at the scene.

Troyer said two employees and a few customers were in the Forza Coffee shop at the time but no one else was hurt. "As you can imagine they are all traumatized," Troyer said.

Authorities scoured the area for the gunman, who is believed to have fled on foot or by car. The suspect was described as a "scruffy"-looking black man in his 20s or 30s, 5 feet 7 to 5 feet 10, wearing a black coat ands blue jeans.

"We are in the process of searching multiple locations," Troyer said.

Nearby McChord Air Force Base was put on alert.

No advance threats
The victims were three males and one female, all officers with the Lakewood Police Department southwest of Tacoma, Troyer said.

There were no specific advance threats against the officers, Troyer said.

A $10,000 reward was being offered for information leading to those responsible.

Brad Carpenter, the founder of Forza Coffee, is a retired police officer himself, NBC News reported. Carpenter started Forza in 2002 and now has 21 stores, primarily in the Tacoma area.

Troyer said there was no known link between the Pierce County slayings and the Oct. 31 fatal shooting of a Seattle police officer who was ambushed as he sat in a parked patrol car with a rookie partner on a Seattle street.

Christopher John Monfort, 41, is charged with aggravated first-degree murder and attempted murder in that shooting. Monfort is also charged with arson and attempted first-degree murder for an October firebombing at a Seattle maintenance yard that damaged several police vehicles.

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