Rescue efforts have resumed aboard the wrecked Italian cruise ship, Costa Concordia, off the coast of Tuscany.
Operations were suspended on Wednesday as the vessel shifted its position. More than 20 people are still missing.
Salvage operators are standing by to start pumping fuel from the ship's tanks to avoid a potential environmental disaster.
The vessel ran aground on Friday with some 4,200 people on board. At least 11 people were killed.
Rescue workers have now almost completed their investigation of the fourth level of the ship, reports the BBC's Bethany Bell at the scene.
Earlier, coastguard spokesman Filippo Marini said the ship had now stabilised.
"The tests during the night were positive and we have divers going down now," Mr Marini told reporters, AFP news agency says.
"We will then use the micro-explosives to open more holes. They will enter inside the ship and search for more people."
A specialist team from a Dutch salvage company is preparing to pump more than 2,300 tonnes of fuel from the ship's 17 tanks.
Mike Lacey, of the International Salvage Union, says the operation could take some time.
"[The fuel] is spread around 17 tanks. The quantities in each tank will obviously be different, and the people there involved in the operation of removing the oil are experts at this sort of thing - and they know exactly what to do," he told the BBC.
"They'll be drilling into each tank, and pumping the oil out and putting it into a barge or a coastal tanker or even a tug.
"These things are all very weather-dependent. If the weather turns against them, then they won't be able to work. So I understand they expect to take a week to two weeks to get all the fuel off."
The ship's captain, Francesco Schettino, has admitted to making a navigational error, Italian media reported.
He told investigators he had "ordered the turn too late" as the luxury ship sailed close to an island, according to a leaked interrogation transcript.
Capt Schettino is under house arrest on suspicion of multiple manslaughter. Prosecutors have also accused him of fleeing the ship before evacuation was complete.
Media reports say the company that owns the ship, Costa Cruises, has suspended Capt Schettino and withdrawn an offer to pay his legal costs.
Italian media have also shown pictures of a Moldovan woman who says she was on the bridge after the ship ran aground, and defended the captain's actions in an interview with Moldovan TV.
The reports say investigators are trying to speak to her.
Meanwhile some 300 Philippine crew members of the Costa Concordia have arrived back in Manila.
They looked visibly shaken by their ordeal, says the BBC's Kate McGeown in the capital.
Some crew members said they did their job well, making sure their passengers were safe, but found the captain and officers had already left the ship by the time the "abandon ship" message was given. They said they felt angry and let down.
"It's... horrible because it is supposed to be the captain to [be] the last one to stay on the ship if there is a collision like this and not the passengers and the crew members," Andrew Bacud, a steward on the ship, told the BBC.