Five people were in custody Thursday after a gunman fired at plainclothes police officers in North Philadelphia and then ran inside a building, triggering a standoff, authorities said.

No officers were injured. The shooting came two weeks after a barricaded gunman armed with an assault rifle wounded six officers before surrendering to end an eight-hour siege in the city’s Tioga section.

The latest shooting occurred about 11:45 p.m. Wednesday at Warnock and Oakdale Streets in the Hartranft neighborhood, police said.

Police Chief Inspector Scott Small told reporters during a briefing at the scene that two plainclothes officers in an unmarked car were witnessing a drug deal at what he called a “known drug location” when a gunman fired three shots at them. The shooter then ran into a corner building with a barbershop on the ground floor and an apartment above it, Small said.

A SWAT team was called in and a standoff ensued as officers urged anyone in the building to surrender and a police helicopter watched from above.

About 1:15 a.m. Thursday, police took four men and one woman into custody without incident. Their names were not released and no charges were immediately filed.

Small said police did not immediately find a weapon and officers began a search of the building Thursday after obtaining a warrant.

During the briefing, gunfire rang out from nearby. “That’s gunshots,” Small said. CBS3 reported that the rear window of a woman’s car was the apparent target of the shooting.

In the Aug. 14 shooting in Tioga, Maurice Hill, 36, has been charged with 11 counts of attempted murder and faces a litany of other offenses, including aggravated assault, assault of a law enforcement officer, and possession of drugs and firearms.

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