SAN FRANCISCO - A 20-year-old suspect was arrested Saturday night for his role in a mall shooting in the US Pacific northwest state of Washington.

Washington State Patrol posted a message on Twitter: "gunman captured tonight by authorities, details forthcoming."

KING-TV in Seattle reported that the man was taken into custody in Oak Harbor, about 47 km southwest of Burlington, where the incident on Friday night killed 5 victims.

The fatalities, initially four women at the makeup department of Macy's department store, one of some 50 vendors at Cascade Mall, were revised Saturday morning to include a male who did not survive life-threatening injuries sustained in the incident.

Sergeant Mark Francis, a public information officer with state patrol, described the suspect as a "Hispanic male wearing grey" Friday night. However, the identity of the suspect in custody less than 24 hours after the shooting is not immediately available.

Security camera images showing the shooter entering the mall apparently without a weapon and then holding a rifle in front of a store were posted by authorities in an effort to seek public help to hunt down the suspect.