An explosion inside a van killed at least 10 people at a military checkpoint in Lamitan City in Basilan on Tuesday, in what officials said may have been a bombing by militants with ties to the Islamic State group.
The blast occurred moments after troops stopped the vehicle and spoke to the driver, according to an official on the island of Basilan and a military incident report.
Later reports pegged the fatalities at 11. But official police body count indicated the fatalities were only 10.
Basilan is a stronghold of the Abu Sayyaf group, which is notorious for kidnapping and banditry, and home of the former "emir" of Islamic State in Southeast Asia, who was killed last year.
Bombings of vehicles are extremely rare in Mindanao despite decades of separatist and Islamist violence and instability that have attracted foreign extremists.
A suspected bomber, a soldier, five militiamen, and four civilians, including a mother and her child, were killed. Others were wounded but the exact number of casualties remained unclear.
Basilan Governor Jim Saliman said he had received reports that the Abu Sayyaf was responsible but did not elaborate.
At Camp Aguinaldo, military spokesperson Colonel Edgard Arevalo said he has spoken to Western Mindanao commander Lieutenant General Arnel dela Vega who pointed to the group of Abu Sayyaf sub-commander Furiji Indama as behind the incident.
"They are losing ground kaya ito ang resort na ginagawa nila ngayon," Arevalo told a news conference.
"Local police and AFP personnel are not stopping their investigation and they are pursuing any leads. We call on our people to be vigilant. We encourage them to notify the PNP and AFP in their locality if they are observation of suspicious looking individuals in their vicinity," he added.
Abu Sayyaf is infamous for taking fishermen and crew from commercial ships as hostages and beheading Western captives for whom ransom is not paid.
President Rodrigo Duterte was on a neighboring island at the weekend and has offered peace talks with several Abu Sayyaf factions.
Citing 74th Infantry Battalion head Lieutenant Colonel Jonas Templo, radio dzBB's Jonathan Andal reported on Dobol B sa News TV that the attack may have been a case of suicide bombing since the driver of the van was among those killed.
UPDATE: 10-taong gulang na bata, kabilang sa mga nasawi sa diumano'y suicide bombing sa isang checkpoint sa Brgy. Maganda sa Lamitan, Basilan. | via @JonathanAndal_— DZBB Super Radyo (@dzbb) July 31, 2018
Autonomous Region in Muslim Mindanao (ARMM) Governor Mujiv Hataman said the suspect "detonated the bomb sensing danger he will be captured."
A military press release said the blast occurred near the Magwakit Detachment in Barangay Colonia in Lamitan City.
Colonel Gerry Besana, spokesperson for the military's Western Mindanao Command (WestMinCom), said five people were also hurt in in the incident.
Dela Vega committed to "exhaust every available resource under his disposal" to identify the perpetrators of the attack at "the soonest possible time," the military press release said. —Reuters with Ferdinandh Cabrera/KBK/RSJ/MDM/KG, GMA News