The ship's owners said they were making efforts to minimise the environmental consequences of the incident [AFP]

The Filipino captain of a ship stuck on a New Zealand reef has been arrested and charged as up to 70 containers fell into rough seas and a black tide of oil washed up on beaches.

Mauro Balomanga appeared in a Tauranga city court on Wednesday amid a heavy police presence. He was charged with operating a vessel in a manner causing unnecessary danger or risk as New Zealand grapples with its worst maritime pollution disaster.

Balomanga was bailed but ordered to reappear on October 19, with the court ordering media not to publish pictures showing his face after his lawyer expressed fears that "the public may take matters into their own hands" with anger running high.

According to local reports, Balomanga had been captain of the ship only since March. The charge carries a maximum penalty of NZ$10,000 ($7,800), or 12 months in jail.

"In the coming days [oil leak] will be noticeable, it will be a large scale environmental disaster"

- Michael Morrah, journalist

Up to 300 tonnes of heavy fuel has leaked into the environmentally sensitive Bay of Plenty since the Liberian-flagged MV Rena hit the Astrolabe Reef, 22km off the North Island coast, last Wednesday.

Overnight, containers began plunging off the stricken vessel in heavy seas, Maritime New Zealand (MNZ) said, but none of them contained hazardous material.

It was highly probably that more containers will topple off because of the severe weather conditions and the vessel's heavy list, MNZ said, despite tying them down tightly to prevent them falling in.

"There are 1,368 containers on board. Eleven containers containing hazardous substances are still on the vessel and are not among the 70 estimated overboard," an MNZ statement said, adding that major shipping had been re-routed.

Oil spill worsens

The amount of oil spilled by the stricken vessel had increased five-fold after it sustained further damage in a storm overnight, Nick Smith, New Zealand's environment minister, said on Tuesday.

"I'd like to acknowledge this event has come to a stage where it is New Zealand's most significant maritime environmental disaster."

Rescue efforts to help wildlife affected by
the spill have taken place [EPA]

Smith made the remarks in Tauranga, where once-pristine beaches have been fouled with oil.

He described as tragic the latest developments, in which up to 350 tonnes of heavy fuel oil leaked into the Bay of Plenty early on Tuesday, but said there was little authorities could do to prevent it.

Earlier, reports said all abroad the Rena had been evacuated.

Michael Morrah, a journalist from New Zealand's TV3 television station, told Al Jazeera on Tuesday that "all the staff [had] been accounted for".

Referring to the oil spill, he said "in the coming days it will be noticeable ... it will be a large-scale environmental disaster".

The animal welfare group Forest and Bird said the timing of the accident, in the middle of the breeding season for birds, was "disastrous".

Greenpeace said it could also affect whales and dolphins calving in the area, as well as other species.

The Rena was built in 1990 and was carrying 1,351 containers of goods when it ran aground, according to the owners.

In addition to the oil, authorities are also concerned about some potentially dangerous goods aboard, including four containers of ferrosilicon.

Source: Al Jazeera and agencies