MARYSVILLE — Police have arrested a Granite Falls man for investigation of killing a man in Marysville on Monday, authorities said.

On Monday night, a woman called 911 to report someone shot her boyfriend at an apartment complex in the 7200 block of 47th Avenue NE, according to Marysville police. When officers arrived on scene, they found a man down in the complex’s parking lot.

Medics attempted life-saving measures, but the Marysville man, 37, died, according to police.

Detectives later learned the suspect had come to the victim’s apartment. They spoke outside. Then the gunman shot the other man and fled the scene, police alleged.

Authorities believe the shooter and the slain man were longtime friends, Marysville police Cmdr. Robb Lamoureux said. The motive for the fatal shooting remained under investigation.

The victim’s girlfriend told investigators who the suspect was. Local police agencies searched for him.

Soon after, Snohomish County sheriff’s deputies found the suspect’s vehicle at his home in Granite Falls, police reported. Detectives got a search warrant for the home in the 8600 block of Highway 92, where the suspect was barricading himself, according to the sheriff’s office.

A SWAT team arrested the suspect for investigation of second-degree murder.

A portion of Highway 92 was briefly closed Tuesday morning as police investigated.