MANILA: The military on Friday said they continued to keep a tight watch over the borders of restive Mindanao following reports that foreign terrorists have succeeded in entering the country through its southern backdoor.

Marine Colonel Edgard Arevalo explained the military wanted to ensure that such terrorists and their local counterparts would not succeed in carrying out another version of the Marawi City siege on May 23, 2017.

“We cannot discount the possibility of foreign terrorists surreptitiously able to enter the country, given our vast and porous borders,” Arevalo said in a press statement.

“That is why we are also keeping a tight watch,” Arevalo added, “over the country’s crevices. We have enhanced our own military and security posture to keep our seaports and airports in check.”

According to Arevalo, the Philippines has an existing trilateral agreement with two of its closest neighbours — Indonesia and Malaysia — for tighter security through coordinated naval and air patrols along their common maritime borders.

But he also emphasised the urgent need for communities in the affected areas in Mindanao to cooperate with the military and other concerned agencies like the police by reporting the presence of “new faces” in their neighbourhoods.

Earlier, Defence Secretary Delfin Lorenzana said the military was checking out reports on the entry of foreign terrorists linked to the Daesh in the Middle East.

Lorenzana said they were not discounting the possibility that such terrorists, in co-ordination with their local counterparts, would do a repeat of the Marawi City siege on May 23 that prompted President Rodrigo “Rody” Duiterte to impose martial law over the whole of troubled Mindanao.

The siege was blamed on the Maute Group and the Abu Sayyaf terrorists so they could establish an Islamic caliphate in Marawi to be used by the Daesh in expanding their operation in Southeast Asia.

Government forces succeeded in liberating Marawi, the capital city of Lanao del Sur province, in October or five months after the siege but not after heavy losses in human lives, massive destruction of the city that also left homeless thousands of resident.

In a joint session in 2017, the Senate and the House of Representatives, dominated by Duterte supporters, extended martial law for another year from Jan.1 to Dec..31, 2018.