Police are investigating an armed robbery in Manoa Monday night involving a teenage victim.

A 15-year-old boy told police that a dark-colored sports utility vehicle drove up next to him as he was walking. One of four males in the vehicle got out and confronted him while a rear-seat passenger flashed a handgun at him. The suspects fled with the victim's backpack.

The robbery was reported to police at 7 p.m.

Police have made no arrests.