-- From Times staff reporter Susan Gilmore:

The slayings of six police officers last year caused the number of deaths due to workplace violence in Washington state to rise to its highest level in more than a decade.

According to the state Department of Labor and Industries, there were 13 on-the-job homicides last year in the state, which includes the six police officers as well as seven suicides. In addition to the police officers, the deaths included retail clerks, a taxi driver, a musician and an armored-car driver.

The next highest year for work-place homicides was 2004, with 11.

In all, according to L&I, there were 62 total fatalities resulting from work-related injuries in 2009. The total was the lowest number in a decade. It includes workers who died of injuries on the job, but doesn't include those who died of illness or heart attack.

There were 69 workplace fatalities in 2008 in Washington state.

Seattle police officer Timothy Brenton was killed Halloween night as he sat in his parked patrol car. Christopher Monfort of Tukwila has been charged in his slaying.

Lakewood police Sgt. Mark Renninger and officers Ronald Owens, Tina Griswold and Greg Richards were shot to death Nov. 29 at a Parkland coffee shop before the start of their Sunday-morning shift. The man accused of killing them, Maurice Clemmons, was fatally shot by a Seattle police officer two days later.

Pierce County Deputy Walter "Kent" Mundell Jr., died several several days after he was shot while on a domestic-disturbance call in Eatonville on Dec. 21. The man who shot Mundell, David Crable, died from gunfire.