A damaged container ship, grounded off the English coast and listing badly, began to lose some of its cargo in heavy winds, and coast guards said Sunday they were on alert because the vessel could break up.

The stricken MSC Napoli was deliberately run aground in waters close to Sidmouth, southwest England, after it was damaged during a storm on Thursday. Navy helicopters rescued the vessel's 26 crew members in rough seas, 45 miles off Lizard Point on England's southwest tip.

French maritime officials said that of the 41,700 tons of merchandise in the ship's 2,400 containers, 1,700 tons were considered dangerous, including explosive and flammable material. The containers also hold motorcycles, car parts and oak barrels.

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Britain's Maritime and Coastguard Agency said more than 150 containers from the ship, which was listing at a 35-degree angle, had slid into the sea as new gales struck the English coast late Saturday.

Oil from the vessel's ruptured engine room tanks was reported to have washed up on a nearby beach, the agency said. It said about 50 coast guards were searching for the lost containers and pollution teams were on standby to handle any spillage.

Coast guard agency spokesman Paul Coley said two of the containers that went overboard contained hazardous materials — including battery acid and perfume products — but that the risk they posed was "minimal."

The 16-year-old vessel is registered in London and was last inspected by the coast guard agency in May 2005, when officials said it met safety standards.

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