GROSSETO, Italy — An echo sounder that tracks water depth had been switched off before the cruise liner Costa Concordia struck a rock and capsized off the Italian coast in January, witnesses at a pre-trial hearing said on Tuesday. The Concordia's captain, Francesco Schettino, is accused of the manslaughter of 32 people, causing a shipwreck and abandoning ship. He has admitted to making mistakes, but says he should not be the only one blamed. The ship's operator, Costa Cruises, a unit of the US-based Carnival Corp, has placed the blame squarely on Schettino and said that nothing discussed in the pre-trial hearing so far concerns its own organization. A panel of court experts told the hearing that the sonar device had been off at the time of the shipwreck, according to people present in the hearing, which was closed to the public because the huge media interest could not be accommodated. The accident triggered a chaotic night-time evacuation of more than 4,000 passengers and crew on the rocky shoreline of the Tuscan island of Giglio. Thirty bodies have been recovered from the wreck and another two people remain unaccounted for. Costa Cruises told the hearing that that the ship had been equipped with more radar systems than needed, and that enough of them had been in operation to meet legal requirements. Codacons, a consumer rights group that has been closely involved in the case, said more information was needed about the state of the ship's equipment before the disaster. — Reuters