A boat which capsized off Bahrain with the loss of at least 57 lives was not licensed to sail as a pleasure cruiser.
Officials revealed that the boat was registered as a fishing boat and had permission only for use as a floating restaurant.
The captain of the boat has been arrested and is being questioned by police.
Local prosecutors said the captain was not licensed to take charge of the boat, and the owners said it may have turned over in calm waters because of the numbers onboard.
Investigators will begin to examine whether the two-deck Arabic dhow was working properly and had met safety regulations.
The boat's owner, quoted by Al Arabiya television, said the traditional wooden dhow may have been overcrowded and capsized when the passengers, who were aboard for a corporate party, gathered on one side.
Some 13 passengers were still missing and Bahrain TV showed pictures of rescue workers using pickaxes to try to break through the bottom of the vessel.
Initial reports were that the dead included 17 Indians, 13 Britons, four South Africans, four Singaporeans, three Pakistanis, three Filipinos, a German and an Irish citizen, later identified as Derek Cunningham, from Drogheda, Co Louth.
The nationality of 11 of the dead had yet to be established.
Rescuers pulled 67 survivors from the water as the rescue operation went through the night, helped by the US navy's 5th Fleet, which is based in the Gulf Arab state.
Officials said 137 people were on board when the boat capsized. Tourism sources said the vessel had a capacity of 100.
The boat trip was for employees of companies involved in a major construction project in Bahrain and their families.
PA