Italian Coast Guard divers battling the elements, including light fuel seeping into the water have found a woman's body in a corridor of a sunken section of the Costa Concordia cruise ship.

The woman's body, one of the 21 still missing, was found Saturday. Italian Coast Guard divers found the woman wearing a life jacket in a narrow corridor near an evacuation staging point at the ship's rear, according to The Associated Press.

The finding raises the death toll in the Costa Concordia cruise ship sinking disaster to 12. Officials believe 20 are still missing.

Coast Guard Commander Cosimo Nicastro told the AP that the body was transported to Giglio, the Tuscan island the Costa Concordia cruise ship was skirting close to when it struck a coral reef, tipped and partially sunk last week.

Nicastro also said Saturday there is no indication heavy oil has leaked from the ship, yet light fuel has been detected and that the substance appears to be diesel. He said the fuel presence, which may be from rescue boats, is very light, very superficial and appears under control.

The ship, which sunk on Jan. 14, was operated by Costa Cruises of Genoa and owned by Carnival Corp. It was carrying more than 4,200 passengers on Friday when it struck the reef just off the Tuscan island of Giglio and capsized. Ship Captain Francesco Schettino was not authorized to take the ship into dangerous waters so close to the shore. He is under house arrest for his actions and may face charges of manslaughter, abandoning ship and causing a shipwreck.

Schettino is suspected of making an unauthorized detour from the ship's programmed route into the dangerous waters. The Italian newspaper Corriere della Sera reported earlier in the week that Schettino may have sailed close to the Tuscan island to delight his head waiter, who is from the island. Others have suggested Schettino may have sailed close to the island to deliver a foghorn-blasting salute to the local population, according to Fox News.

Schettino's behavior after the wreck has been as curious as the ship's fatal path. A new audiotape was released Thursday detailing the first reported contact between port officials and the Costa Concordia. Schettino was heard on the tape telling port officials the ship only had a blackout more than 30 minutes after it crashed into the coral reef. He apparently neglected to mention that the cruise ship was sinking.

The recording, according to Fox News, was made at 10:12 p.m. Schettino told the port official was he was checking to see why the ship had a blackout. He didn't tell the official that the ship had struck the coral reef, and that it had been involved in a chaotic disaster for more than a half hour. Some 20 minutes after that conversation with the port officials is when the cook says Schettino ordered dinner.

An audio tape released earlier in the week detailed tense conversation between Schettino and a Coast Guard officer responding to the accident after Schettino had abandoned the ship and was in a lifeboat. The Italian Coast Guard officer told Schettino to get back on the ship he had abandoned.

You go on board! Is that clear? Do you hear me? the officer shouted to Schettino, who was safe in a lifeboat away from the ship as passengers tried to escape, while others had already perished inside.

It is an order, the Coast Guard officer shouted. Don't make any more excuses. You have declared 'abandon ship.' Now I am in charge.

Schettino responded saying the ship was too dark to return to, while also noting the ship was dangerously tipping.

I am here with the rescue boats, Schettino said. I am here. I am not going anywhere. I am here to coordinate the rescue.

What are you coordinating there? the Coast Guard officer said. Go on board! Coordinate the rescue from aboard the ship. Are you refusing?

Said Schettino: Do you realize it is dark and here we can't see anything?

Said the Coast Guard officer: And so what? You want to go home, Schettino? It is dark and you want to go home? Get on that prow of the boat using the pilot ladder and tell me what can be done, how many people there are and what their needs are. Now!

There are already bodies now, Schettino.