Lakewood, Washington (CNN) – Four Lakewood police officers were fatally shot Sunday in what police said was an ambush in a coffee shop.

The officers were sitting in the coffee shop before the start of their shifts, reading on their computers, when the shooting occurred, Sheriff’s Department spokesman Ed Troyer said. Authorities believe the officers were meeting and going over cases or doing paperwork, he said.

A gunman came inside and shot all four officers, Troyer said. Two coffee shop employees and other customers inside the shop were unharmed, said Troyer, who said the shooting “was a targeted, selected ambush.”

“As you can imagine, they are traumatized,” he said of those inside the coffee shop. “Some are in shock.”

Families of the officers have been notified, Troyer said. All of the officers — three males and a female — were in uniform, wearing vests and had marked patrol cars parked outside, he said.

A $10,000 reward was offered for information leading to an arrest, Troyer said.

Update:

One of four police officers killed in an ambush at a coffee house Sunday fought with the gunman and may have wounded him before the officer died just outside the doorway, a sheriff’s spokesman said.

Pierce County sheriff’s spokesman Ed Troyer told reporters that investigators were asking area medical providers to report any people wounded by gunshots.

Troyer said investigators believe two of the officers were shot dead while sitting in the shop, and a third was killed after standing up. The fourth apparently struggled with the gunman out the doorway and “gave up a good fight,” getting off a few shots before he was either shot there or succumbed to earlier wounds.

Update:

Troyer said authorities are seeking Maurice Clemmons, 37, of Pierce County as part of their investigation, though he did not identify Clemens as a suspect.

“We believe he is intentionally avoiding us,” Troyer said, identifying Clemmons as a “person of interest.”

Clemmons has “extensive violent criminal history from Arkansas, including aggravated robbery and theft,” the sheriff’s department said in a statement. He also was recently charged in Pierce County for assaulting a police officer and the rape of a child, according to the statement.