Italian Environment Ministerdeclared a state of emergency on Monday that fuel has begun leaking from the overturned ship and 198 drums containing hazardous substances from the ship have been lost at sea.

Environment Minister?Corrado Clini said after the cruise ship Costa Concordia hit a rock off the coast of Tuscany early on January 13.

The Costa Concordia struck a rock, left, on the island of Giglio, January 13, 2012. [Italian Ministry of the Environment]

The ship capsized immediately offshore of the island of Giglio, which is part of the Tuscan Archipelago National Park.

"The environmental risk for the island of Giglio is very high. The goal is to prevent the fuel from the ship coming out: we're working on that," the minister said from the city of Livorno, on the Tuscan coast opposite the island. "The action is urgent, we hurry."

Most of the more than 4,200 passengers and crew were rescued and taken to the island, as well as to the mainland 16 kilometers away.

To date, at least six people have died and 64 were injured, with 15 still missing.

The ship is reported to be slipping off the Giglio rocks. Search-and-rescue efforts have been suspended as seas near the island grow rougher.

The salvage company Smit has been contracted to remove the fuel from the Costa Concordia. The company has said crews will begin pumping operations after the search and recovery is completed. Smit estimates it will take more than two weeks to pump the 2,400 tons of fuel off the vessel.

Workers with the Environment Ministry have placed absorbent containment booms around the wreck, which leaking a slick of light fuel. The biggest concern is that the ship's heavy fuel could leak before it can be removed from the ship.