A Liberian-flagged cargo ship is stuck 14 miles off the coast of New Zealand after it ran aground on a reef earlier this month. A crack from the deck to the waterline is clearly visible on the Rena, which has spilled about 350 tons of fuel oil into the sea.

The captain and second officer of the ship face criminal charges as the Rena continued to break up in rough seas after the Oct. 5 accident, according to the Associated Press.

Maritime New Zealand, which is managing the emergency response, described the crack as a “substantial structural failure,” warning that the stern may break away.

Click play to watch a video report on the doomed tanker.

Three tugboats were mobilized to hold the stern on the reef or tow it to shallow water, according to the agency. Volunteers have been brought in to clean up oil spilling from the ship.

“This is a unique situation. Volunteers have not been used before in oil spill cleanups, and it shows the level of community commitment to this significant environmental issue,” National On Scene Commander Nick Quinn says.

Salvage teams were winched aboard Rena last Friday morning, and they were attaching four platforms to the port side of the vessel. The platforms will provide a flat surface for fuel-pumping operations from the port tanks, according to Maritime New Zealand.

Rough seas have made salvage work difficult. Fewer than 85 tons of oil have been removed from the listing ship, and an estimated 1,400 tons remain aboard, according to a report from the Los Angeles Times. The oil that has leaked has killed nearly 1,300 seabirds. The operation has been hindered by rough seas.

Maritime New Zealand issued a statement Oct. 12 about the ship’s precarious position:

“The Rena has suffered substantial structural failure, with a crack appearing in the No. 3 cargo hold on the starboard side. This has been caused by the movement of the vessel as the stern, which has remained afloat, [shifts] with the waves while the front part of the ship remains stuck on the reef. There is a concern that the stern of the vessel may break away. … Naval architects are working on possible scenarios.”