EDMONDS — Before a fatal stabbing in Edmonds, the suspect had been “blowing up” his ex-girlfriend’s phone, upset about her friendship with Bret Northcutt, according to a search warrant filed in court this week.

Edmonds police now believe Ian Bramel-Allen, 48, was “lying in wait” for the targeted attack on Northcutt at a WinCo on the evening of April 19.

At 8:23 p.m., Northcutt parked his Kia Sorento outside the store at 21900 Highway 99, according to court papers. He spent about 19 minutes inside. Meanwhile, video surveillance showed Bramel-Allen walked over to the Kia and tried to open the passenger door, but found it locked, according to the warrant filed in Snohomish County Superior Court. The suspect reportedly stashed a backpack in bushes outside the store, for reasons that aren’t explained in the warrant, then stationed himself beside a Redbox kiosk near the exit.

Northcutt exited the store carrying a brown grocery bag and walked back to his car, police wrote. Bramel-Allen followed at a distance of 20 to 30 feet, and when they got close to the car, he ran up and repeatedly stabbed Northcutt in the torso. The attack lasted about 18 seconds. Northcutt tried to walk away, but collapsed.

The suspect then got into the wounded man’s car, driving past Northcutt on the ground, according to Edmonds police.

Police arrived to find witnesses performing first aid on the man, according to court documents. Northcutt, of Portland, was pronounced dead shortly after being loaded into an ambulance. He was 37.

The Snohomish County Medical Examiner’s Office confirmed Thursday the cause of death was “sharp force injuries.” The manner was homicide.

The Kia Sorento was registered to a woman whose daughter is Bramel-Allen’s ex-girlfriend, who happened to be at the Swedish Edmonds hospital next door, police wrote.

Nearly six hours later, police found the Kia Sorento in Seattle near 15th Avenue E and East Galer Street, on the east side of Volunteer Park. A 911 caller guided police to the suspect, who tried to flee on foot. Bramel-Allen stabbed himself “multiple times” in the neck before surrendering, police wrote. He was then arrested for investigation of first-degree murder, first-degree robbery and theft of a motor vehicle.

An ambulance took the suspect to Harborview Medical Center. While in the hospital, Bramel-Allen reportedly asked investigators, “Is Bret OK or not?”

The suspect began crying when detectives told him Northcutt was deceased, court papers say.

In a recorded interview with investigators, Bramel-Allen stated he didn’t mean to kill Northcutt, but that he “just saw red” when he saw him walking to his car, according to court documents. In the same interview, Bramel-Allen reportedly said something along the lines of “I plead guilty to everything,” court documents say.

Police filed a search warrant Sunday to obtain Bramel-Allen’s DNA to compare to blood and trace samples found in the Kia Sorento and on Northcutt’s clothes and the suspect’s backpack that was stashed near the parking lot.

Bramel-Allen remained under guard Thursday at Harborview, police said. He had not been booked into jail and hadn’t been in front of a judge.

Court records suggest Bramel-Allen had no violent felony history in the state.

Edmonds detectives were still working on the case this week. Tips can be directed to policetips@edmondswa.gov, or detective Patrick Clark at patrick.clark@edmondswa.gov or by calling 425-771-0285.

Maya Tizon: 425-334-3939; maya.tizon@heraldnet.com; Twitter: @mayatizon.