An 81-year-old man has been shot in IJsselmonde in the third such incident in the Rotterdam district in 12 days.

Passers-by found the severely wounded man early on Thursday morning and alerted emergency services, local broadcaster Rijnmond reported.

It is the third shooting in the district in little over a week and police are not ruling out that the perpetrator is choosing his victims at random, although other scenarios remain open.

On December 21 a man was shot and killed at Reyerdijk in the district and a week later a 58-year-old man was found on a cycle path on Roelantpad. He also died from his injuries.

None of the incidents seemed to be gang-related as none of the victims had criminal links, police said.

Police have released footage of a man they want to interview in connection with the shooting of the 58-year-old. The public prosecution office has since put up a reward of €30,000 for the tip off that leads to the man.

An investigation will have to show if the incidents are related, police said.