The stern section of the stricken container vessel Rena that has been stranded on a rock reef for six months after it ran aground off the coast of New Zealand finally submerged and is now visible beneath the water on Astrolabe Reef.

The 47,230-ton Liberian-flagged ship has been stuck on the reef, about 14 nautical miles (22 km) from Tauranga, on the east coast of New Zealand's North Island, since it ran aground Oct. 5 last year, according to Reuters.

Authorities claim it to be one of the nation's worst environmental disasters as the ship broke into two parts, increasing ecological hazards. While the bow section still remains above water, the ship's stern shifted and sank as a result of nearly 40-foot-high waves and 31 mph winds.

Nearly eleven containers containing tons of oil, fuel, timber, wool, plastic, bangs of milk powder washed up on the shore and debris still floats around the remains of the stricken container ship.

The Bay of Plenty and Coromandel communities are advised that the sinking of the stern section will likely to result in the loss of more debris and small amounts of oil into the sea, which may then come ashore, Maritime New Zealand said.

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