Salvage crews raced against time Monday to prevent a second disastrous oil spill off the picture-perfect coastline of Mauritius, with a damaged tanker carrying nearly 2,000 tonnes of fuel at risk of splitting apart.

The bulk carrier MV Wakashio ran aground on July 25 with 4,000 tonnes of fuel and began seeping oil last week, staining coral reefs, mangrove forests and tranquil lagoons in an unprecedented environmental catastrophe for the Indian Ocean archipelago nation.

More than 1,000 tonnes has already oozed from the stranded ship, causing untold damage to protected marine parks and fishing grounds that are the backbone of Mauritius' economy
More than 1,000 tonnes has already oozed from the stranded ship, causing untold damage to protected marine parks and fishing grounds that are the backbone of Mauritius' economy AFP / STRINGER

More than 1,000 tonnes has already oozed from the ship, its Japanese operator says, causing untold ecological damage to protected marine parks and fishing grounds that form the backbone of Mauritius' economy.

Fuel was slowly airlifted from the ship Monday by helicopter to the shore, but efforts to pump more from the hold had been thwarted by rough seas and strong winds.

The weather is also fanning the oil slick further up the coast and is not forecast to improve until evening
The weather is also fanning the oil slick further up the coast and is not forecast to improve until evening AFP / -

The weather, which had fanned the oil slick further up the coast, had improved enough for a barge to approach the ship and safely pump out 500 tonnes on Monday, Prime Minister Pravind Jugnauth said.

That left nearly 2,000 tonnes of oil on the ship, he said at a press conference late Monday.

Thousands of volunteers, many smeared head-to-toe in black sludge, have marshalled along the coastline in a desperate attempt to hold back the oily tide
Thousands of volunteers, many smeared head-to-toe in black sludge, have marshalled along the coastline in a desperate attempt to hold back the oily tide L'Express Maurice / Daren Mauree

Jugnauth had earlier warned that cracks in the hull were worsening, and there was a very real chance the boat could split.

Drone images show vast amounts of oil leaking from a bulk carrier off Mauritius after it ran aground in the southeast of the island. Ecologists fear the ship could break up, which would cause an even greater leak and inflict potentially catastrophic damag
Drone images show vast amounts of oil leaking from a bulk carrier off Mauritius after it ran aground in the southeast of the island. Ecologists fear the ship could break up, which would cause an even greater leak and inflict potentially catastrophic damage on the island's coastline. LASENTINELLE

"We are in an advanced fracturing process. The bulk carrier does not have much time ahead of it," said one scientist working on the emergency effort, speaking on condition of anonymity.

Fuel was being airlifted by helicopter to the shore, but efforts to pump more from the hold were being thwarted by rough seas and strong winds
Fuel was being airlifted by helicopter to the shore, but efforts to pump more from the hold were being thwarted by rough seas and strong winds L'Express Maurice / Daren Mauree

Divers have reported fresh cracks in the hull, while creaking sounds from the vessel could be heard from the southeast shore, where a major clean-up operation is underway to remove treacly sludge coating miles of Mauritius' previously unspoiled coastline.

Japan on Monday dispatched a six-member team, including members of its coastguard, to assist.

France has sent more than 20 tonnes of technical equipment -- including 1.3 kilometres (0.8 miles) of oil containment booms, pumping equipment and protective gear -- along with technical advisers from nearby Reunion, a French Indian Ocean island.

A map of Mauritius
A map of Mauritius AFP / Anne-Sophie THILL

A spokesman at Mitsui OSK Lines, which operates the Wakashio, owned by another Japanese company, Nagashiki Shipping, told AFP it would send a team of experts as soon as Tuesday if they tested negative for coronavirus.

"Nagashiki Shipping deeply apologise to the people of Mauritius and will do their utmost to protect the environment and mitigate the effects of the pollution," the Wakashio's owner said in a statement Monday.

The bulker struck a reef at Pointe d'Esny, an ecological jewel fringed by idyllic beaches, colourful reefs, sanctuaries for rare and endemic wildlife, and protected wetlands.

Aerial images show the enormity of the disaster, with huge stretches of crystal-clear seas around the marooned cargo ship stained a deep inky black.

Thousands of volunteers, many smeared head-to-toe in black sludge, have turned out along the coast since Friday, stringing together miles of improvised floating barriers made of straw in a desperate attempt to hold back the oily tide.

"My friends and I came here today to lend a hand because of the degradation of our environment. The entire marine ecology has been affected by the heavy oil spilled from the ship. We are very affected by this problem," said Eldridge Larhubarbe, a student.

Police are expected to take statements from the captain and crew of the Wakashio after launching an investigation. Detectives boarded the ship on Sunday and seized the log book and black box.

Pressure is mounting on the government to explain why more was not done in the two weeks since the vessel ran aground.

Mauritius and its 1.3 million inhabitants depend crucially on the sea for food and ecotourism, having fostered a reputation as a conservation success story and a world-class destination for nature lovers.

The spill is a double blow for tourist operators who had hoped foreign tourists could soon return.

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