LYNNWOOD — Snohomish County sheriff’s detectives are asking for help finding a robber who hit three convenience stores in the Lynnwood area over the past few weeks.

Most recently, the robber walked into the gas station at the corner of 164th Street SW and 36th Avenue West near Lynnwood. It happened about 11 p.m. Monday, sheriff’s spokeswoman Rebecca Hover said.

Surveillance video shows the man walking up to the counter, looking at the camera and then pulling a red bandanna up over his chin. He pulled out a knife from under his jacket, grabbed some cash and ran away.

Two similar robberies were reported nearby in August, Hover said.

On Aug. 8, a man walked into a minimart along Cypress Way around 11:30 a.m., showed a knife and fled with the cash. The same thing happened about 9:30 p.m. on Aug. 19 along 176th Street SW.

No one has been injured in any of the robberies, Hover said.

The suspect is described as black and in his 20s or 30s. He is more than 6-feet-tall and weighs between 230 and 260 pounds. In the robberies, he wore dark clothing and at least once donned a baseball cap and bandanna.

He might be connected to a white Ford Mustang made sometime after 2000, Hover said.

Anyone with information is asked to call 425-388-3845.

Rikki King: 425-339-3449; rking@heraldnet.com

Watch surveillance video of one of the robberies at youtube.com/heraldnet.