The calls were fast and frantic as gunshots echoed in the background. "Priority -- shots fired! Shots fired!" a voice said, getting louder with each declaration.

Other voices followed, at times speaking over one another. One repeated the address where gunfire broke out -- over and over.

Police scanner captured the chaotic first few minutes when gunfire erupted while officers were serving a narcotics warrant at a row house in North Philadelphia. On scanner traffic, a flurry of grim announcements came from unidentified officers and dispatch.

"Officer down!" one voice said.

"We need SWAT!" another person yelled.

"Get me SWAT, ASAP! Long guns, ASAP!" one loudly interrupted.

Others implored faster action, the urgency evident in their words.

"This is the second call ... shots fired at police!" one said.

"I've got an officer shot, radio!" one voice said, at times cracking. "Radio, listen. I've got one officer shot, one officer shot, radio!"

The gunman injured six officers after he opened fire Wednesday afternoon in a standoff that lasted nearly eight hours. Philadelphia Police Sgt. Eric Gripp announced his arrest early Thursday, ending a chaotic and tense day that left a neighborhood on edge.