Jack Byers went missing around 12:55 a.m. on Sunday, February 22, near the Old Bridge in Coleraine.

Officers want to contact anyone who saw him or spoke with him from Saturday evening, February 21, through early Sunday morning.

Two males walking a dog in the town centre at about 12:44 a.m. spoke briefly with Byers before they left the area. Police consider them key witnesses.

Anyone with details should call police on 101, quoting reference CW 77- of 22/02/26.