New Zealand's shipping authorities have cordoned off a Liberian-flagged container ship that has grounded on a reef off the east of the North Island as they attempt to assess whether it poses an environmental risk.

The 236-meter cargo ship Rena struck the Astrolabe Reef, about 12 nautical miles off the coast near Tauranga Harbour, at around 2. 20 a.m. Wednesday and was listing, said a statement from Maritime New Zealand (MNZ). (Xinhua/Reuters Photo)

None of the 25 crew aboard the 47,000-tonne vessel were reported injured, it said.

A light sheen of oil was visible around the ship, but it was thought to be hydraulic oil from the engine and was not considered "a significant environmental risk at this point," it said.

MNZ had activated its Maritime Incident Response Team (MIRT) of experts to provide technical advice and oversight.

MNZ's 25-strong National Response Team of oil spill specialists was setting up a command center in Tauranga, and would lead the response in the event of a significant spill from the ship.

MIRT incident controller Renny van der Velde said the plans being put in place by the oil spill response team would form a safety net in the event of any spilled oil.

"While the aim is to remove the vessel with no oil spilled, it is important to have contingency plans in place in case something goes wrong."

The vessel owner -- reported to be the Israel-based Ofer Brothers Group, one of the world's largest private shipping firms - - was responsible for coordinating a salvage plan.

MNZ was also working with wildlife experts from Massey University and the Department of Conservation, which advised there were no immediate concerns for marine life, to prepare for any possible spill.

An MNZ maritime safety inspector aboard the vessel had assessed the damage and advised that the ship had several breaches to the hull, affecting cargo holds on the port side.

The ship was on a 10-degree list, but was stable on the reef, and fuel in tanks on the port side was being transferred to the starboard side as a precautionary measure, said the MNZ statement.

Pumps were working remove water from the cargo holds.

The ship's captain was in discussion with the ship's owner and salvage experts to assess how best to move the ship off the reef, but a decision was expected to take "some time."

The local Bay of Plenty Regional Council staff has ordered a 1- kilometer exclusion zone around the vessel, which was fully laden.

Tauranga harbour master Carl Magazinovic he had received reports of "sightseeing vessels" near the grounded ship, potentially causing safety issues and disrupting response efforts.

"This situation is expected to continue for some time so we will be monitoring movement of vessels around the area, and anyone found breaching the exclusion zone could face a fine of up to 20, 000 NZ dollars (15,220 U.S. dollars)," said Magazinovic.

Michael Hodgins of the Mediterranean Shipping Company, which chartered the 21-year-old Rena, told Radio New Zealand it was carrying timber, milk powder, meat and fish.

He said the crew would have been familiar with the route it was taking, which started in Singapore and included ports in Australia as well as New Zealand before heading back to Sydney, a journey usually taking about six weeks.

VietNamNet/Xinhuanet