Six people are dead and a cruise liner captain is being held on suspected manslaughter after the ship struck rocks or a reef and overturned off the Tuscan coast Friday. The search for 16 people who were still unaccounted for continued in rough seas Monday.

A prosecutor confirmed Italian authorities were also investigating accusations that the captain abandoned the cruise liner before all of its passengers had been evacuated, the penalty for which is up to 12 years in prison under Italian navigation code.The captain was reportedly seen by Coast Guard officials fleeing the scene as passengers still were being evacuated.

Captain Francesco Schettino has said he did not abandon the ship early and did everything in his power to save lives.

There were also questions about why the cruise ship was navigating so close to the eastern coast of the tiny Giglio island, where rocks and reefs make the waters dangerous for ships.

The cruise liner’s Italian owner issued a statement Sunday saying that there appeared to be “significant human error” on the part of Schettino, and that it “resulted in these grave consequences.”

The Coast Guard had retrieved the ship’s “black box,” which holds the recording of the vessel’s navigational details.

The maritime attorneys at Maintenance and Cure represent cruise vessel crewmembers and passengers who have been injured in accidents on a cruise ship.