A man stabbed four people to death in Washington state on Tuesday morning as sheriff’s deputies were on their way to serve him a domestic violence protection order, authorities said. The suspect was later shot dead by a deputy who arrived at the scene.

According to the Pierce County Sheriff’s Office, deputies first received a call around 8:40 a.m. that a 32-year-old man was violating a no-contact order at a home on the Key Peninsula, northwest of Tacoma. After confirming the order had not yet been formally served, officers headed to the address to deliver it.

While they were on the way, fresh reports came in around 9:30 a.m. that the man was stabbing people outside the home. The first deputy reached the location within minutes and shot the suspect, who died at the scene. Three victims were found dead there, while another died on the way to hospital.

Court records show that the suspect’s mother, who lived at the home, had obtained a one-year protection order against her son last May, citing mental health and substance abuse issues, past physical aggression and repeated threats. She said he had been mentally and emotionally abusive, damaged property and hurt her cat, adding that she was an elderly disabled woman being taken advantage of.

The order required him to stay away from his mother and not possess dangerous weapons, and to follow a mental health treatment plan. It remains unclear why the order had not yet been formally served.

A nearby resident said he heard several gunshots echo through the area, followed by continuous sirens, before learning of the tragic incident.