A 36-year-old man entered a Gaithersburg 7-Eleven early Thursday, walked around the store and — without provocation — slashed a clerk to death with a box cutter, according to Montgomery County police officials and court records.

Shaun D. King was booked into the Montgomery County Detention Center on first-degree murder charges and was being held without bond.

The victim, Abdul Ghaffar, 63, of Gaithersburg, had worked at a number of area 7-Eleven stores. “He was a nice guy. He was not aggressive. He was passive,” said Prakash Dulal, who works at a different 7-Eleven in Gaithersburg. “I don’t think he would have any enemies.”

Court records show that King had been placed on 18 months’ probation in early 2013 after pleading guilty to trying to flee from police in a burglary case. He also has a record of arrests on drug and assault charges, according to court records.

In the homicide case, police filed an arrest affidavit Thursday that describes the broad outlines of their allegations.

Shaun David King (Montgomery County Police Department )

About 1:49 a.m., police received a call about a stabbing at the 7-Eleven at 9051 Snouffer School Rd., in the northern part of the county outside the core of Gaithersburg. As officers arrived, they saw King leaving the store with what appeared to be blood on his pants and hands, according to the affidavit.

“As the defendant was being detained, officers also observed what appeared to be blood on the defendant’s sweatshirt, shoes and sunglasses,” the affidavit states. After King was handcuffed, he fled but was caught after a brief foot chase, police said.

Officers found a bloody, “box-cutter style knife” inside a pocket of King’s sweatshirt, court papers say.

Inside the store, police found Ghaffar “bleeding profusely from injuries to his neck, chin and both wrists,” according to the affidavit. He was taken to Suburban Hospital in Bethesda, where he died.

Another worker at the store, who had called 911, told police that he witnessed the attack. “He observed the defendant attack the victim, unprovoked,” the affidavit states.

Detectives also reviewed surveillance video from inside the store, which shows King enter the store, “ultimately attack the victim and exit the store.”

King “denied knowledge of the incident” when he was questioned by detectives, according to the affidavit.

Police have not provided a motive in the killing but said it did not appear to be robbery.

King’s probation stems from a Nov. 22, 2012, incident in Rockville, when a victim told police that he’d seen a man at his window about 6:30 p.m., yelled at him and then ran outside to see the man climbing over a fence, according to Montgomery court records. Police eventually found King near the house and put him in a squad car. King opened the door as the car was moving and tried to flee, but he was captured again, according to court records.

On Jan. 3, 2013, King pleaded guilty to second-degree escape, according to court records. He was sentenced to 21 days in jail — time that he had served after his arrest — and was placed on 18 months’ probation, according to court records.

Jennifer Jenkins contributed to this report.

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