Six crew have been kidnapped from a Vietnamese bulker off the Philippines.

A group of about 10 armed men boarded the 5,600-dwt Royal 16 (built 2011) on Thursday, according to Zamboanga coast guard station commander Jerome Cayabyab.

Another crewman, the electrician, suffered an arm injury in the incident off Sibago Island, ABS-CBN reported.

The abducted men were confirmed as the master, the chief mate, the second and third officers, the bosun and a rating.

A passing cargo vessel informed the coast guard about the raid.

No group has yet claimed responsibility, but the Abu Sayyaf terrorist group has been linked to the attack.

The vessel is owned by Quysang Trading Shipping of Thai Binh province, Vietnam.