In the moments after Cassidy was hit, scores of police officers swarmed 20 square blocks in the northern edge of Philadelphia, nearby schools were locked down, and Mayor Street, Police Commissioner Sylvester M. Johnson, and others made their way to Albert Einstein Medical Center, where the 25-year veteran of the force was taken.
Cassidy, 54, a married father of three, was listed in critical condition Wednesday night after surgery to relieve swelling in his brain. Cardinal Justin Rigali also went to the hospital to be with the officer's family.
Cassidy was the third police officer to be shot this week and the second within 12 hours.
Police released two portions of a surveillance tape that show the beginning of the robbery, at 10:30 a.m., and its immediate aftermath.
In the first section, a hooded man is seen coming into the shop and lurking, as if casing the store at 6620 N. Broad St. Then he pulls out a handgun and waves it as he bulls his way toward the cashier. The last few frames of the section show Cassidy approaching the front door.
The gunman shot Cassidy in the head at close range, Johnson said during a news conference at Police Headquarters. "He assassinated him," Johnson said. "This is very emotional for me."
The second section of the videotape shows the outside of the store. The robber stoops down, picks up Cassidy's handgun, and runs off.
Cassidy had routinely checked the store because it had been robbed Sept. 18, apparently by the same man, Johnson said. Someone in the parking lot had alerted Cassidy to the robbery, he said, and the officer pulled out his gun as he approached.
