Rough seas in the Bay of Plenty have caused the rear section of the Rena to sink.
The sinking was confirmed during an overflight of the vessel on Wednesday at 4pm.
The Rena has been lodged on Bay of Plenty's Astrolabe reef since October and broke into two pieces in January.[image:4930:full]
Maritime New Zealand says the sinking of the stern section will likely result in the loss of more debris and small amounts of oil into the sea, which may come ashore in the Bay of Plenty and Coromandel.
It says a light sheen of oil has been observed stretching for about 1km north-west of the wreck.
The forward section of the vessel is holding on the reef, but has suffered further damage in Wednesday's high seas.
A wave of over 12 metres was recorded at the reef Tuesday night, and seas of eight to nine metres were recorded on Wednesday.
The Thames-Coromandel council says it is still expecting debris to come ashore on its coastline from the shipwreck of the Rena.
No oil or debris has yet reached Coromandel's rocky shores but winds are still blowing in that direction.
Thames-Coromandel mayor, Glenn Leach, says it is likely some oil or debris will arrive over the next few days and Maritime New Zealand is keeping response teams on standby.
Mr Leach says the winds are swinging to the north-east and pushing any debris in the sea towards Waihi Beach.
Mr Leach says searches of five areas between Whitianga and Whiritoa since first light have not resulted in reports any oil or container debris.
However, the risk to boats from drifting material remains, so the annual Easter yacht race from Auckland to Tauranga is cancelled.