Nairobi, Feb 19 (IANS) Pirates have hijacked a boat with four American nationals on board off the coast of Oman, the US embassy in Nairobi said Saturday.

‘Preliminary reports indicate that a US-flagged vessel named the Quest has been hijacked in the Arabian Sea. There were four US citizens on board,’ an embassy spokesman was quoted as saying by the Daily Telegraph.

East African maritime expert Andrew Mwangura said the boat was sailing from India to Salalah in Oman when the pirates struck Friday afternoon.

Advocacy group Ecoterra said that the Americans were being held hostage.

The Quest was attacked by pirates in the Indian Ocean and the four Americans on board were being held hostage, the group said in a statement.

The 58-foot yacht was owned by Jean and Scott Adam. The couple began their world trip in 2004, according to their website. It was not immediately known if the couple were sailing the yacht at the time of the attack.

Pirates in Somalia are still holding two South Africans seized from their yacht late last year. In November, another gang released British couple Paul and Rachel Chandler after holding them captive for more than 14 months.