"The MV Action was released by pirates, " said Andrew Mwangura, head of the Seafarers Assistance Program in Mombasa, Kenya.

CNN: U.S. military considers options to deal with Somali pirates

"We may have bad news, " said Andrew Mwangura of the Kenya Seafarers Association.

CNN: Somalia asks Russia for help with pirates

Andrew Mwangura, of the Mombasa-based East African Seafarers' Assistance Programme, told Reuters news agency it is UK-owned but operated by Italians.

BBC: Somali pirates seize more vessels

The last contact with the ship was late last week, and it was unclear exactly when the hijacking took place, said Andrew Mwangura, the head of Kenya Seafarers Association.

CNN: Pirates strike again off Somalia; ship from Yemen seized