Philadelphia police on Wednesday identified a man who was fatally shot by police last month in Frankford as Terrell Mitchell, 35. They said the shooting happened after Mitchell threatened and chased a SEPTA employee with a knife.

Staff Inspector Sekou Kinebrew, a police spokesperson, said the department is not releasing the name of the officer who shot Mitchell because “we are currently investigating threats made against him.” He declined to detail the threats, which occurred after the shooting.

Police Department policy is to release the name of an officer in a police shooting within 72 hours of the incident unless there is a threat against the officer or family members.

The shooting of Mitchell occurred about 5 p.m. May 29 in a SEPTA parking lot on the 1500 block of Pratt Street, near the Frankford Transportation Center.

It was the 10th of 11 police shootings this year in which a civilian was struck, four of them fatally, Kinebrew said. The 15th District officer who shot Mitchell is 29, has been on the force for six years, and is on desk duty while the shooting is investigated, Kinebrew said. The name of the other officer, who did not fire a shot, is not required to be released, he said.

Kinebrew said there was a delay in the release of Mitchell’s name and in the determination of whether police could release the name of the officer who shot him because “our resources became taxed” during the continued unrest in the city amid protests following the May 25 killing of George Floyd by Minneapolis police.

In the shooting of Mitchell, police said two uniformed officers were on patrol in their car when they saw a male SEPTA employee being chased on a sidewalk and into the parking lot by a knife-wielding, shirtless man. The officers drove into the lot, got out of their car, drew their service weapons, and ordered the man to drop the knife, police said.

Mitchell, still armed with the knife, “advanced toward” one officer, who “began a tactical retreat, back pedaling approximately 192 feet,” and who ordered the man to drop the knife, police said.

Police said Mitchell ignored their commands and lunged at the officer with the knife. The officer fired his weapon once, striking Mitchell in his torso, police said.

Mitchell was taken by police to Jefferson Torresdale Hospital, where he was pronounced dead shortly afterward. The knife was recovered at the scene, Kinebrew said.

Emanuel Mitchell, one of Mitchell’s brothers, said Wednesday that his brother had mental health and drug issues, and that he believes his brother was high on drugs that day. He said he did not know if Mitchell, who worked on and off as a laborer, had any problems with the SEPTA employee. His brother was living with a girlfriend in the Oak Lane area and may have been visiting their father in Frankford that day, he said.

He questioned why police didn’t use a Taser or pepper spray on Mitchell, or shoot him in a leg or tackle him. “My brother should be in jail, he shouldn’t be in a casket,” Emanuel Mitchell said.

Kinebrew said that he did not know if Mitchell was on drugs, and that it would be part of the investigation. He declined to respond to the brother’s other comments.

In a statement, Police Commissioner Danielle Outlaw said, “We recognize the gravity and seriousness of the use of lethal force by a police officer.” She said the shooting will continue to be investigated and that police “are aware of a video circulating on social media that depicts a portion of the incident, and reaffirms the facts we provided on the date of the discharge.”