Two eagle-eyed police officers witnessed a double shooting in Kensington early Friday evening and quickly chased down and arrested the suspected shooter, authorities said.

The cops were driving behind two men traveling in a Cadillac around 6 p.m. when they turned right on Amber Street from Cambria. At the corner, a man on a bike pulled a gun and began firing shots into the driver's window of the Cadillac, wounding both men, Chief Inspector Scott Small said.

Small said the officers chased the shooter on foot to Monmouth Street near Amber, where they saw him discard a handgun. They caught up with the 24-year-old man and arrested him nearby, and then recovered the five-shot revolver near Monmouth Street, Small said.

The men in the car continued down Amber Street until crashing into the back of a van near the intersection of Auburn, Small said. The 22-year-old driver, suffering a head wound, was rushed to Temple University Hospital, where he was pronounced dead at 6:35 p.m.

The passenger, a 27-year-old man, was wounded in the left shoulder, Small said. He was in stable condition at Temple.

Small said the officers who witnessed the shooting were in a marked car and in uniform at the time, but the shooter apparently either didn't see them or was brazen enough to commit the crime in front of them.

He praised their relentless pursuit of the shooter.

"After the shots were fired, the officers immediately [went] into pursuit," he said.

Both officers were taken to the Homicide Unit to be interviewed. Police also had a second man in custody in connection with the shooting.