MANILA/JAKARTA: Militants seized four Indonesian crew of a tugboat in the southern Philippines on Friday night, the third attack on slow moving vessels in about a month, a military spokesman said on Saturday, as troops battled rebels on a nearby island.

Another man, who was shot and injured, and five other crew members managed to escape and were taken to Malaysia by its maritime police along with the two vessels, the Indonesian Foreign Ministry said.

It said the attack happened on Friday evening as they were heading to Tarakan on Indonesia’s Borneo island from Cebu in the central Philippines. The wounded Indonesian is in a stable condition.

Major Filemon Tan said seven gunmen in a blue speed boat attacked two Indonesian flagged tugboats off the Philippines’ southernmost island of Sitangkay in Tawi-tawi, near the border with Malaysia’s eastern Sabah state, and took the four crew.

“We don’t exactly know who took them but the only lawless group operating in that area is the Abu Sayyaf,” Tan said, adding 10 Indonesians and four Malaysians were also abducted in two separate incidents early this month in the south.

The Indonesian Foreign Ministry issued a statement said four Indonesian crew were taken captive after gunmen attacked two tugboats, TB Henry and TB Cristy, on their way to Kalimantan from Cebu. Six other crew were left behind but one was shot.

“He is in stable condition now,” the Foreign Ministry said, adding Malaysian water police evacuated the wounded crew to a hospital in Lahad Datu in eastern Sabah state, where the two tugboats were towed to safety.

The military said the militants have been targeting foreign crew of slow moving tugboats because they could no longer penetrate resorts and coastal towns in Sabah due to increased security.

The incident comes after the kidnapping in March of the 10-member crew of an Indonesian tugboat and barge in the often insecure border region between the southern Philippines and Indonesia.

In that case, the owner of the tug boat received telephone calls, purportedly from the militant group Abu Sayyaf, demanding a ransom.

Authorities believe the 10 Indonesians are held captive in the southern Philippines.

The Philippine military said troops are monitoring areas where the new kidnap victims could be brought, including Jolo island in Sulu province, where Abu Sayyaf militants are believed to be holding foreign hostages in jungle camps.

Philippine military spokesman Brig. Gen. Restituo Padila said officials were assessing if the Abu Sayyaf or other armed groups were involved in Friday’s kidnappings.

The Indonesian Foreign Ministry said the government will take steps to address the frequent occurrence of piracy in the region and invite neighboring countries to improve security.