The Rena captain has pleaded guilty to all charges in Tauranga District Court today (Wednesday), the New Zealand Herald reported.

The captain was originally charged under section 65 of the Maritime Transport Act with "operating a vessel in a manner causing unnecessary danger or risk" and under the Resource Management Act relating to the "discharge of harmful substances from ships or offshore installations."

The ship's second officer, who was also in court, faced the same charges, but he entered no plea on the second charge (Resource Management Act).

However, the captain faced new charges in December, including three alleged offences under the Crimes Act and a charge of "willfully attempting to pervert the course of justice."

Each charge carried a maximum penalty of seven years' imprisonment.

The New Zealand media is complying with court ruling to withhold the identities of the two until sentencing in May.

MV Rena, a very large cargo vessel, crashed into Astrolabe Reef off Tauranga in New Zealand's Bay of Plenty in October, causing a major oil spill and a massive environmental disaster for the country. The vessel has since split in two, and some of the cargoes have toppled over to the ocean. Recovery efforts for the remaining cargoes are under way.