A tramper is missing in Fiordland.
The man, who was intending to climb the Devil's Armchair, was reported overdue early yesterday.
The search began yesterday morning.
A police spokesperson said before first light today, an aerial search using thermal and night vision technology was carried out.
A land search and rescue dog team is searching along the northern part of the Milford Track, while alpine search and rescue teams will search what was believed to be the man's intended route.
Further aerial searches are planned.