It happened just after 3:30 p.m. on 6th and Somerset streets.
Police say its ATV detail was in the area when officers spotted a dirt bike rider.
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"They were following him on his dirtbike, which we know is illegal in the city," noted Deputy Commissioner Mike Cram with Philadelphia police.
Officers followed the rider to a parking lot, investigators say.
"The officer, when he stopped, that's when the uniformed officer confronted him," Cram said.
Authorities say police confronted the dirt bike rider to inform him what he was doing was illegal, which is when he allegedly displayed a gun.
An officer then fired at the suspect at least two times, investigators say. The suspect was struck by the gunfire.
Authorities say the suspect was then taken to Temple University Hospital in critical condition.
Police say its dirt bike unit has been out in the city attempting to curb dirt biking and ATV riding, which has caused chaos in some neighborhoods.
"They disturb the peace and quality of our neighborhoods. They don't care they are a public safety risk and this is a prime example of why we do enforcement against them," said Cram.
So far this year, authorities say they have confiscated over 180 dirt bikes or ATVs.
Police are still investigating this incident.
A gun was recovered at the scene, investigators say.
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