A 24-year-old man has confessed to killing three people in the IJsselmonde area of Rotterdam in less than two weeks, the public prosecutor said on the first day of his trial.

Sendric S, 24, was arrested on January 2, the day he shot his third victim, a 81-year-old man. He has now confessed to shooting all three, including a 58-year-old man on December 21 and a 63-year-old man just a week later.

In all three cases the victims, who seemed to have been selected at random, were approached and shot from behind. The motive for the killings is unknown. A psychiatric report from the Pieter Baan Centrum may provide clues, the prosecutor said.

One of the tip-offs that led to S came from the person who sold him the gun via Snapchat, a 20-year-old from Amsterdam who is also facing charges.

Tip-offs enabled the police to track S to a relative’s apartment just hours after the third murder. They were also able to retrieve the gun after S attempted to get rid of it by throwing it from the balcony.

Part of the €30,000 reward will be issued, but no information about the informant will be given for privacy reasons, the department said.

The case will continue on June 24.