A diver has stopped a leak of diesel from a boat that sank in Coromandel Harbour.
Waikato Regional Council said the diver blocked the breathers of the pleasure craft's fuel tanks, which had lost a small amount of diesel.
The 10m boat was towed into the harbour by the Coastguard last night after breaking down nearby.
After it was moored close to the ferry wharf near Te Kouma, the vessel sank and diesel began to leak.
There was unlikely to have been any environmental impact from the leak, which was tiny, the council's on-scene commander Dave Lovatt said.
Iwi and shellfish farmers were told of the leak.