Wreckage from the Russian nuclear-powered submarine Kursk is being towed into port after a salvage operation succeeded in lifting the submarine from the floor of the Barents Sea.

Approximately 20,000 tons of metal from the Kursk, a vessel that was once one of the premier submarines in the Russian navy, is now on its way back to port after being lifted from the waters of the Barents Sea.

Early Monday, salvage workers from the Dutch company Mammoet began raising the submarine a few meters per hour.

Twenty-six cables from a giant barge that was positioned directly over the sunken vessel were attached to the hull of the submarine. Using the cables, the barge hoisted the Kursk to the surface.

The barge is towing the submarine into a port near Murmansk in the far north of Russia, where the nuclear reactors on board will be removed. After this, the submarine will be decommissioned.

For safety reasons, the front section of the submarine, where the explosions occurred, was sawed off and will remain on the ocean floor. Russian officials say it is too badly damaged to be raised at this time, but they say they plan to raise it in the future.

Officials had originally said the sub would be raised September 15. But that date was set back a number of times due to various technical delays and bad weather.

Explosions in the torpedo bay caused the Kursk to sink in August of last year. All 118 people on board were killed. Russian authorities are investigating what caused the explosions but no official reason has yet been given.

During a meeting with the families of those who died on the Kursk, Russian President Vladimir Putin promised that he would raise the submarine and recover the bodies of those inside.

Russian officials and environmentalists have expressed concern about the environmental consequences of leaving the submarine's nuclear reactors on the sea floor. They have detected no problems, but they fear that if it were left on the ocean floor the reactors could begin to degrade.