The victim, Nasser Abdul, 25, was standing in front of a store in Bagua District here, tracking a kidnapper holding out in the area when the gunman, disguised as a pedicab driver, approached him from behind and opened fire with a .45 automatic.
Abdul, who sustained a gunshot wound in the back of his head, died on the spot.
The victim, a Maguindanaon, was killed a week after Cotabato City Mayor Muslimin Sema, who is the secretary-general of the Moro National Liberation Front, warned to use "extra-legal means" to stop criminals, including kidnappers, from operating here.
Abdul, according to the local police, is one of more than 20 civilian informers who have volunteered to help the city government get rid of lawless elements here by gathering information on their activities and their whereabouts.
The victim was credited for past arrests of notorious Pentagon gangmen holding out in the city. — John Unson