VIDEO: Hundreds of Officers Gather in Pittsburgh to Honor Slain K-9

Under gray skies and lowered flags, hundreds of law enforcement officers — many flanked by their K-9 partners — gathered in the cold Thursday morning to pay respects to slain Port Authority police dog Aren, reports the Pittsburgh Tribune-Review .

"It changes your life," said Indiana Township Officer Scott Palmer, who spoke at the memorial, of becoming a K-9 officer. "Not only do you know your dog, your dog knows you."

The estimated 350 law enforcement officers came from as near as their respective Pittsburgh police zone stations and as far as Meadville to pay their respects and support Aren's handler, Port Authority of Allegheny County (PA) Police Department Officer Brian O'Malley. Nearly 150 officers joined a red and blue lights-flashing procession that drove to the memorial just off North Shore Drive.

The procession began on the East Busway. It was near the East Busway in Wilkinsburg that Aren was stabbed to death Sunday while trying to apprehend a suspect. Police shot and killed the man, Bruce Tyrone Kelley Jr.

The deadly incident began about 3:30 p.m. Sunday when two Port Authority officers came across Kelley and his father, Bruce T. Kelley Sr., drinking in a gazebo near Linear Trail. Both men fought with officers before fleeing. The officers called for backup and attempted unsuccessfully to TASER Kelley Jr. before they released Aren. The man pulled out a knife and stabbed the dog in the mouth before two officers, including O'Malley, shot him.

Aren, a 5-year-old German shepherd, came to Pittsburgh from the Czech Republic when he was about 13 months old, according to Port Authority police Chief Matthew Porter.