EVERETT — A Snohomish County sheriff’s detective did double duty Monday detaining an armed robbery suspect in Everett.

Detective Dave Bilyeu was driving past the intersection of 37th Street and Rockefeller Avenue when he saw two men in a shoving match shortly after 6:30 p.m.

One of them — an Everett man, 28 — was dressed in all black. He wore a ski mask over his face.

When the detective activated the siren and emergency lights on his unmarked vehicle, the masked man ran and jumped into a red pickup truck.

The suspect drove about a block before pulling over and surrendering.

The alleged robbery victim told the detective he was walking out to his car and the suspect confronted him with a handgun and demanded his wallet. The victim grabbed the gun and began punching the suspect.

When the deputy drove by, the suspect dropped the gun and ran. A dark ski mask was found on the floor of the pickup.

The gun was found near the scene of the scuffle. It turned out to be an airsoft gun, which looked like a real handgun.

Two witnesses observed the holdup.

Everett police officer Aaron Snell said the city appreciated the extra help.

“We work closely with other jurisdictions,” Snell said. “It’s always nice when we can assist them and thy can assist us.”

The suspect was booked into the Snohomish County Jail for investigation of robbery.

That might not be all of his legal troubles.

Mukilteo police are investigating a robbery that occurred earlier Monday.

In that case, a man in a black ski mask and driving a red pickup held up a man who was walking a dog in the 8900 block of 49th Avenue W. The victim told police he handed over his wallet after being confronted by a man pointing a handgun at him.

“We are working with Everett police to see if the two cases are linked,” Mukilteo police Sgt. Cheol Kang said.

Eric Stevick: 425-339-3446; stevick@heraldnet.com.