The captain of the Costa Concordia, the liner which capsized off the coast of Italy last month killing at least 25 people, made a series of errors that were compounded by failures onshore by the ship's operators, according to prosecution documents.
Prosecutors accuse captain Francesco Schettino of causing the accident by bringing the giant vessel too close to shore where it struck a rock that tore a large gash in the hull, causing water to flood into the engine rooms.
He is under formal investigation in the case, accused of multiple manslaughter and abandoning ship before the evacuation of more than 4,200 passengers and crew was complete.
On Thursday, prosecutors added two new counts to the charge sheet, accusing Schettino of abandoning incapacitated passengers and failing to inform maritime authorities. Officials confirmed that tests showed he was not on drugs at the time of the accident.
First officer Ciro Ambrosio and seven other ship's officers and executives of the operator Costa Cruises are also under investigation.
They include the vice president of Costa Cruises, Manfred Ursprunger and Roberto Ferrarini, head of the company's crisis unit, with whom Schettino was in contact during the evacuation.
Pretrial hearings, including an investigation of the ship's black box recorders, are due to open on March 3.
The Costa Concordia foundered and capsized metres from the shore off the Tuscan island of Giglio on January 13. At least 25 people died in the accident and a further seven are unaccounted for.
Eight bodies, including that of a five year-old girl, were found by divers on Wednesday on the submerged deck of the liner, which lies on its side in some 20 metres of water.
CONFUSION AND DISTRACTION
Schettino is blamed for bringing the ship near to the rocky shore in order to perform a display manoeuvre known as a salute, but prosecutors have also pointed to wider failures in the management of the accident.
In documents filed on Wednesday notifying Schettino of the impending investigation, prosecutors say Schettino slowed the ship down while he was having dinner on the night of the accident, then sped up to 16 knots to make up time, despite being in shallow water.
They also say his nautical charts were not appropriate and not detailed enough to reveal obstacles including the rock on which the fatal impact occurred.
The report also points to the large number of people in the bridge area at the time of the accident, including Domnica Cermotan, a friend of Schettino's. They say this generated confusion and distraction for the captain.
It says he failed to perform appropriate manoeuvres to avoid the collision, did not activate procedures to seal the ship, and did not take charge of the crew during the operation. He also took too much time to sound the general alarm and order the evacuation of the ship.
The prosecutors also blame Costa's crisis unit of being culpably unaware of the real situation on board the ship and of falling to properly verify the information provided to it by Schettino.
The unit limited itself to bureaucratic aspects...and to the future prospects of repairing the ship, the report said.
As well as the official investigation, Costa and its parent company Carnival Corp, the world's largest cruise operator, face a wave of civil suits from the victims' families and from passengers and crewmembers aboard the ship.
(Writing By James Mackenzie)