At least one person was struck and injured at the Tacoma Mall, Pierce County Sheriff’s Sgt. Darren Moss said.
The News Tribune reports people called 911 just after 7 pm to say multiple shots were fired.
Hundreds of shoppers sheltered in place or hid inside stores, which immediately went into lockdown.
More than 60 law enforcement officers from Tacoma, Pierce County, Lakewood, Puyallup and the Washington State Patrol are on scene.
“We’re sending people inside to do a coordinated search,” Moss said.
The Tacoma Mall is the city’s largest shopping mall, with more than 100 stores.