The Upper Perk Police Department received a call at 7:41 p.m. Tuesday about a family member armed with a sword threatening to harm others at 8th Street and Long Alley.
Responding officers encountered the male suspect in Long Alley, carrying a samurai-type sword. He has been identified as 27-year-old Trey Bartholomew.
The DA's office said, according to the investigation, an Upper Perk police officer arrived on the scene with his vehicle lights and siren activated.
The DA said Bartholomew charged at the officer. Police opened fire.
Neighbors reported hearing three shots, and then Bartholomew was struck, the DA's office said.
The DA's office did not say if it was one or more officers who fired the shots.
Police officers immediately rendered first aid, but Bartholomew was pronounced dead at the scene by EMS.
A sword was recovered by the body.
The DA's office said per protocol for officer-involved shootings in the county, Montgomery County Detectives responded to the scene to investigate the shooting.
The names of the police officers involved are not being released at this time.
The investigation is ongoing.
Anyone with any information is asked to contact Montgomery County Detectives at 610-278-3368.