A group of 21 Filipino seamen were abducted by pirates off the dangerous waters off Somalia after their Philippine-operated bulk carrier was hijacked Wednesday, the Philippine government said on Thursday.

The latest hijacking incident, taking place a few days after 37 Filipino seamen were freed by their captors after alleged payment of ransom, brought to 66 the total number of Filipino seafarers being held by Somali pirates.

Vice President Noli De Castro, concurrent presidential adviser on overseas Filipino workers, said the Filipino crewmen of MT African Sanderling were seized by heavily armed men while navigating through the coast of Somalia.

He said carrier was a Philippine-operated one, but a foreign ministry official said later that it was operated by Japanese.

The Philippine government is closely coordinating with the employers and manning agency of the Filipinos, he said.

De Castro, meanwhile, said the government is still awaiting further developments on the latest Somali piracy case.

"Nonetheless, I want to reiterate our appeal to the international shipping companies to take extra precautionary measures and to strictly follow the directive to limit voyages to the "safe zone" or the Maritime Security Patrol Area," De Castro said.

Coalition naval forces led by the United States, Britain and France are patrolling and giving assistance to vessels passing the Maritime Security Patrol Area.

The Philippine government has been in a dilemma on how to provide protection to its thousands of seamen. It says banning Filipinos from certain risky regions would be difficult because of the rapid mobility of the sailors and its lack of ability to monitor their movement.

(Xinhua News Agency October 16, 2008)