Pirates hijacked a Greek-owned bulk carrier on Thursday in the Gulf of Aden near Yemen, a Kenyan maritime official said today.

"Red Sea Spirit was taken by gunmen off the Yemeni coast last Thursday. She is flying the Panama flag," said Andrew Mwangura, coordinator of the Kenya-based East African Seafarers' Assistance Programme. "She is a Greek-owned bulk carrier." News of the seizure only emerged on Saturday, he said.

Somali pirates have continued to defy foreign navies patrolling the waters off the Horn of Africa and are holding at least 13 vessels and more than 200 crew.

There was a pause in hijackings during monsoon rains, but the sea gangs have stepped up attacks in the past two months, extending their range to as far as the Seychelles, to evade the naval vessels.

Piracy attacks around the world numbered 324 during the year to Oct. 20, according to figures from the ICC International Maritime Bureau's Piracy Reporting Centre.

Attacks by Somali pirates in the Gulf of Aden and the east coast of Somalia, numbered 174, with 35 vessels hijacked and 587 crew taken hostage.

Nearly 20,000 ships pass through the Gulf of Aden each year, heading to and from the Suez Canal.