A man fatally stabbed four people before being shot dead by a sheriff’s deputy outside a home northwest of Tacoma, Washington, on Tuesday morning, authorities said.

The Pierce County Sheriff’s Office said in a news release that deputies initially responded to reports made at around 8:40 a.m. local time Tuesday that a 32-year-old man was violating a no-contact order. They obtained a copy of the order, learned it was not valid because it had not been served on the suspect, and headed to the scene to provide it to him.

“It was an order, but it just hadn’t had that final step of being served yet, so the deputy’s intent was to serve that order today,” Officer Shelbie Boyd, a spokesperson for the Tacoma Police Department, told reporters near the scene.

While en route, additional reports came in that the man was stabbing people outside the home, the sheriff’s office said. The first deputy arrived within about three minutes and shot the suspect, who was pronounced dead at the scene.

Three of the stabbing victims were pronounced dead at the scene and a fourth died while being taken to a hospital, the sheriff’s office said.

The stabbings took place in a cul-de-sac on the Key Peninsula, located near Gig Harbor and about 30 miles southwest of Seattle.

No names were released, and Boyd told reporters that the relationship of the suspect to the victims was not immediately known. It was unclear if the four victims resided at the home, Boyd said. She could not confirm if any of the stabbings occurred inside the home itself.

When reached by CBS News, the FBI deferred all questions regarding the investigation to the sheriff’s office.

Pierce County court records show that a woman who lived at the address last May obtained a one-year protection order against her 32-year-old son. She wrote that he had mental health and substance abuse issues, had previously pushed her, and more recently had threatened her by saying that her “grave has been already dug up.”

The son had been “threatening me, abusing me both mentally and emotionally. Doing witchcraft/occult behavior and doing rituals in my home,” the woman wrote. “Damaging personal belongings. Hurting my cat…I am an elderly disabled woman and he is taking advantage of me and my health.”

The records show that the son had notice of a hearing before the issuance of the restraining order, but did not appear for it. The protective order required him not to possess dangerous weapons; to stay 1,000 feet from his mother, her vehicle and her address, which they had shared; and to comply with a previously prescribed mental health treatment plan, including medication.

It was not immediately clear why the attacker had not previously been served with the protection order. Typically in Washington state, someone who obtains such an order can request that law enforcement deliver it to the subject of the order or hire a private investigator or “process server” to do so. Not knowing the location of the subject of the restraining order can delay that.

Chris Cardenas, who lives just a couple minutes driving from the street where the stabbings occurred, said he was washing his truck in his driveway when he heard the gunfire.

“All of a sudden, I just heard like a series of gunshots,” he said. “You could really hear it echoing through the trees.”

Sirens then sounded nonstop for about 40 minutes, he said.

“I immediately knew something was up because I’ve never heard gunshots out here,” he said.

He went over to the cordoned-off scene and saw ambulances, a forensics bus and dozens of police vehicles, he said, adding that he couldn’t have braced himself “for how tragic the news would be.”