Police in the Philippines investigating the fatal New Year's Eve shooting of a local official did not have to look further than the last photograph he took. It led to the arrest of two suspects.

The picture, taken outside the man's house in Manila, shows a man aiming his gun from behind the victim's smiling three-member family, seconds before he was shot.

The relatives – Reynaldo Dagsa's wife, daughter and mother-in-law – are seen standing beside the family car, which has its lights on, and the gunman, wearing a baseball cap, is bracing himself against the vehicle, pointing his gun at Dagsa. His face is slightly obscured by the gun. In the right-hand corner of the photograph is a man police identified as the assassin's lookout.

The car was parked along an alley outside the Dagsas' house.

Police said Dagsa was shot seconds after the photo was taken and died of wounds by the time he reached hospital. His family gave police the photo, which ran on the Philippine Daily Inquirer's front page.

Caloocan city police chief, Jude Santos, said a man identified as the gunman in the picture was arrested yesterday. His accomplice was arrested in a separate raid in Manila the same day.

Santos said the main suspect was a car thief who was out on bail and likely sought revenge against Dagsa for ordering his arrest last year.

Dagsa's wife and daughter told reporters he had asked them to wake him up before the stroke of midnight so he could join in the usually noisy New Year's Eve street revelry that comes with lots of firecrackers.

The family members said they did not hear a gunshot because the firecrackers were exploding all around them. They only saw Dagsa falling to the ground after he was hit and they rushed him to hospital.