US mudslide death toll reaches 33

The death toll from the landslide that hit a US town last month has risen to 33, authorities said.

Snohomish County medical examiner’s office said all but three have been identified.

Many died of multiple blunt force injuries in the March 22 mudslide that crushed a residential area north-east of Seattle in Washington state.

The number of missing is 12, said Shari Ireton, spokeswoman for Snohomish County sheriff’s office.

That figure does not necessarily correlate with the number of dead, said Kelly Stowe, a spokeswoman for the medical examiner’s office. The missing list remains fluid as names are added and removed.

As the search continues in the debris for bodies, the Army Corps of Engineers is working on a berm – a rock and gravel barrier – to prevent the flow of the Stillaguamish River from flooding parts of the debris field near the town of Oso.

Engineers hope to finish the berm in a week.

Searchers have had to contend with treacherous conditions, including household chemicals, septic tanks, petrol and propane containers. When rescuers and dogs leave the site, they are hosed off by hazardous materials crews.