NAIROBI, Nov. 30 (Xinhua) -- Suspected Somali pirates have hijacked a Greek tanker off the coast of the Horn of Africa country, a regional maritime official confirmed on Monday.

Andrew Mwangura, the East Africa Coordinator of Seafarers Assistance Program (SAP) said the Piraeus-registered Maran Centaurus was seized late Sunday with its 28 crew members on board, including Greeks, Filipinos and a Romanian.

Mwangura said the Greek vessel which was traveling from Kuwait to the United States was hijacked off the eastern coast of Somalia.

"This is the biggest vessel to have been hijacked by Somali pirates recently and followed that of Sirius Star. Maran Centaurus was heading to United States from Kuwait when she was hijacked off the eastern coast of Somalia," Mwangura told Xinhua by telephone from Mombasa.

Reports say the Maran Centauros has a crew consisting of nine Greek nationals, 16 Filipinos, two Ukrainians and one Romanian.

The vessel's first mate informed the ship-owner Christen Navigation of the incident, saying the crew was well. He also told the owner that the pirates had directed the tanker to sail to a Somali port.

Piracy has become rampant off the coast of Africa, especially in the waters near Somalia, which has been without an effective government since 1991.

Ransoms starting out in tens of thousands of dollars have climbed into millions.

Somalia is at the entrance to the Gulf of Aden, which leads to the Red Sea and the Suez Canal, one of the world's most important shipping channels.

The Gulf of Aden, off the northern coast of Somalia, has the highest risk of piracy in the world. About 25,000 ships use the channel south of Yemen, between the Red Sea and the Arabian Sea.