Military officials are on high alert after suspected Abu Sayyaf militants attacked a South Korean cargo ship and abducted its South Korean skipper and a Filipino crewman on Thursday, off Bongao town in Tawi Tawi province.
According to Straits Times, regional military spokesman Major Filemon Tan said that the ship was on its way to South Korea from Australia when around 10 gunmen boarded the MV Dongbang Giant using ropes from a speedboat.
However, except the two crewmen, others were not seized and one person managed to call his family who in turn reported the assault to authorities.
The victims who got abducted are identified as skipper Chul Hong and Filipino crewman Glenn Alindajao.
Movements of ships in the area where the incident took place are being closely monitored since most of the kidnapping by Abu Sayyaf militants have been happening there. The spokesperson has also confirmed that naval patrols have been strengthened in the region, reported the news agency.
"We do our best to secure that area but it's a wide body of water," said Tan.
The Abu Sayyaf group which is linked to the Islamic State in Iraq and Syria (ISIS) have been responsible for a series of abductions and have developed a reputation as ruthless kidnappers in recent times.
The rise of kidnapping incidents at sea has prompted Indonesia, the Philippines and Malaysia governments to try to coordinate maritime patrols in order to put a check on the militants' activities. In a trilateral maritime security meeting in Bali, the countries agreed to let each other enter one another's waters in times of emergency.