At least three people were killed and one critically wounded in a shooting at a shopping mall north of Seattle and at least one suspect remains at large, authorities in the US state of Washington said.

The Washington State Patrol said on Twitter the four were shot on Friday at the Cascade Mall in Burlington, about 105km north of Seattle.

It previously said four people had been killed, reports Al Jazeera.

Sergeant Mark Francis said authorities were searching for a “Hispanic male wearing grey” who was last seen walking towards a highway from the mall.

He also said it wasn't immediately known if there was more than one gunman involved.

Medical workers have entered the mall to treat the wounded.

Governor Jay Inslee said in a statement the state patrol and local law enforcement were on the scene to locate the shooter and clear the area.

BDST: 1229 HRS, SEP 24, 2016
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