Police cars were seen speeding toward the scene in the North Philadelphia neighborhood of Tioga-Nicetown as armored vehicles and police in tactical gear converged on a street.
About a dozen officers were seen taking cover behind cars as other officials surrounded a home with guns drawn.
One woman said she heard over 100 gunshots and saw people running for their lives.
“I heard so many gunshots… I’m scared,” she told ABC Philadelphia station WPVI.
Agents from ATF (the Bureau of Alcohol, Tobacco, Firearms and Explosives) are at the scene to assist, a spokesperson said.
Gripp urged residents to avoid the area.
This story is developing. Please check back for more updates.
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