A salvage operation has successfully raised the wreck of the ill-fated Costa Concordia is set to begin more than two years after it sank off the Italian island of Giglio.

The high-risk operation on Monday raised the rusting hulk of the 114,500-tonne vessel, which will now begin its final journey to the shipyard where it was built.

We're talking about a floating city kitted out for thousands of passengers, with gallons of pollutants such as oils, detergents and sewage chemicals still inside.

Giorgia Monti, Greenpeace

The operation to salvage the 290-metre long ship's wreck was unprecedented in its scale.

"The ship is upright and is not listing either longitudinally or latitudinally. This is extremely positive," said Franco Porcellacchia, the engineer in charge of the salvage, the Reuters news agency reported.

"The most critical phase will be the first day, raising the wreck for the first time. Refloating a passenger ship this large has never been attempted before," South African Nick Sloane, who is in charge of the salvage, told AFP news agency before Monday's successful attempt.

The Costa Concordia was rotated upright in September and was sitting on an underwater platform.

The disaster in January 2012 left 32 people dead, with one body still left unfound.

Italian officials told the AP news agency that a search operation for the remains of a missing Indian national, Russel Rebello, would begin as soon as the cruise liner was towed away.

In a worst-case scenario, some environmentalists warn the hull could break apart and spill its rotting innards into what is one of Europe's largest marine sanctuaries.

"We're talking about a floating city kitted out for thousands of passengers, with gallons of pollutants such as oils, detergents and sewage chemicals still inside," said Giorgia Monti from Greenpeace, which is observing the operation.

Environmental risks

Salvage crews said the Concordia would be towed  240km north to the port of Genoa, where it is expected to arrive later this month.

Salvage costs so far are estimated at around $1.5bn.

The ship's captain Francesco Schettino is currently on trial for manslaughter, causing a shipwreck, and abandoning the vessel before all of the passengers had been evacuated.

Four other crew members and a Costa Crociere executive have plea-bargained and the company has accepted limited responsibility as Schettino's employer.

The four-day journey to Genoa is fraught with possible environmental hazards, with warnings that some of the 100 tonnes of fuel and 263,000 cubic metres of polluted water flooding its lower decks could leak out.

Costa Crociere insists the amount of leakage will be comparable to that discharged by any vessel crossing the area.

Source: Agencies