The Costa Concordia, the Italian luxury cruise ship that ran aground off the west coast at Giglio island, is almost submerged in the Mediterranean Sea.

Around 4,200 passengers were believed to have been onboard the ship when it ran aground after hitting a rock Friday night. Six of the passengers have been confirmed dead so far. It is certainly one of the worst cruise liner disasters of all time, according to maritime specialists.

According to the Italian coast guard officials, the number of missing passengers has increased from 16 to 29. They include 10 Germans, six Italians, two French couples, two Americans and a Peruvian.

The rescue squad is researching the areas submerged in the water using micro-cameras and checking thousands cabins inside the cruise ship.

The conditions inside are disastrous. It's very difficult. The corridors are cluttered and it's hard for the divers to swim through, Rodolfo Raiteri, head of the coast guard's diving team, told AFP.

Check out the recently released underwater pictures of the Costa Concordia.

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Costa Concordia
A breach is seen underwater on the side of the Costa Concordia cruise ship that ran aground off the west coast of Italy, at Giglio island in this photo released on January 16, 2012. Rescue squads used controlled explosions on Tuesday to enter a sticken Italian crusie liner in the increasingly despairing hunt for survivors as authorities almost doubled their estimate of the number missing to 29 people. Reuters
Costa Concordia
A side of the Costa Concordia cruise ship is seen underwater after it ran aground off the west coast of Italy, at Giglio island in this photo released on January 16, 2012. Rescue squads used controlled explosions on Tuesday to enter a sticken Italian crusie liner in the increasingly despairing hunt for survivors as authorities almost doubled their estimate of the number missing to 29 people. Reuters
Costa Concordia
A part of the Costa Concordia cruise ship is seen underwater after it ran aground off the west coast of Italy, at Giglio island in this photo released on January 16, 2012. Rescue squads used controlled explosions on Tuesday to enter a sticken Italian crusie liner in the increasingly despairing hunt for survivors as authorities almost doubled their estimate of the number missing to 29 people. Reuters
Costa Concordia
A side of the Costa Concordia cruise ship is seen underwater after it ran aground off the west coast of Italy, at Giglio island, in this photo released on January 16, 2012. Rescue squads used controlled explosions on Tuesday to enter a sticken Italian crusie liner in the increasingly despairing hunt for survivors, as authorities almost doubled their estimate of the number missing to 29 people. Reuters
Costa Concordia
An Italian Coast guard diver inspects the Costa Concordia cruise ship that ran aground off the west coast of Italy, at Giglio island January 16, 2012. Over-reliance on electronic navigation systems and a failure of judgement by the captain are seen as possible reasons for one of the worst cruise liner disasters of all time, maritime specialists say. Reuters
Costa Concordia
A breach is seen underwater on the side of the Costa Concordia cruise ship that ran aground off the west coast of Italy, at Giglio island January 16, 2012. Over-reliance on electronic navigation systems and a failure of judgement by the captain are seen as possible reasons for one of the worst cruise liner disasters of all time, maritime specialists say. Reuters
Costa Concordia
A breach is seen underwater on the side of the Costa Concordia cruise ship that ran aground off the west coast of Italy, at Giglio island January 16, 2012. Over-reliance on electronic navigation systems and a failure of judgement by the captain are seen as possible reasons for one of the worst cruise liner disasters of all time, maritime specialists say. Reuters
Disasters Coast Guard