At least six Philadelphia police officers were shot on Wednesday in a drug raid in the north of the city, and a shooter continued to fire from a residential building, according to police and local media.
Philadelphia Police said the officers did not have life-threatening injuries.
Local television station Fox 29 said five officers were taken to two local hospitals, while a sixth officer had been injured in a vehicle incident while responding to the shooting.
NBC 10 said a male suspect was in a building and exchanging gunfire with police.
Fox 29 reported that two drugs squad officers were holding individuals they had arrested inside the same building as the shooter, with two officers barricaded inside.
The shooter was moving up and down the interior stairs in the building shooting into the ceiling and outside, Fox 29 reported.
Television images showed hundreds of police surrounding the building, many with guns drawn, with stations saying a SWAT team was negotiating with the shooter.