Missing boy could be anywhere in South Island

The estranged stepfather of a missing 11-year-old boy could be anywhere in the lower South Island, according to the police.

John Beckenridge, who's 64, and his stepson Michael Zhao-Beckenridge have been missing since Friday when he wasn't at school when his mother went to pick him up.

There has been one confirmed sighting of the pair in the Catlins area on Monday and the police have also received a number of unconfirmed sightings in the southern South Island, over the past few days.

Detective Sergeant Mark McCloy said the police are continuing to appeal to Mr Beckenridge to make contact.