Italian searchers have found three more bodies in the wreckage of the Costa Concordia cruise ship that capsized off the coast of southern Italy.

A civil protection agency spokesman says the bodies were found by a remote-controlled robot which was searching inaccessible parts of the ship. It is unclear when they will be recovered.

A total of 28 bodies have been recovered since the Costa Concordia ran aground off the island of Giglio on January 13. Four remain missing.

The ship, which was carrying 4,200 passengers and crew, capsized when the captain deviated from his planned route and struck a reef, creating a huge gash in the ship.

Italian prosecutors have placed the ship's captain, Francesco Schettino, under house arrest, accused of manslaughter and abandoning the vessel.