A 20-year-old man sustained life-threatening injuries after he was stabbed in Federal Way on Tuesday afternoon.

At about 2:45 p.m. June 8, officers responded to multiple reports of a stabbing in progress in the 1900 block of S. 320th Street, according to Cmdr. Kurt Schwan of Federal Way police.

As officers arrived, they were told the suspect was being restrained by passersby.

Officers detained the 44-year-old male suspect, while other officers began life-saving measures for the victim, a 20-year-old man, Schwan said.

Fire personnel and medics responded, taking over medical treatment for the victim. The victim sustained life-threatening injuries and was transported to Harborview Medical Center by medics, Schwan said.

Detectives from Federal Way’s Criminal Investigation Section are assisting with the investigation.

The relationship between the suspect and victim, and the motive for the stabbing, is unknown at this time, Schwan said.