government soldiers
Government soldiers take part in a firefight with Muslim rebels from the Moro National Liberation Front (MNLF) in Zamboanga city in southern Philippines Sept. 12, 2013. Reuters/Erik De Castro

At least seven Philippine soldiers were killed and 13 were injured in a clash with the Abu Sayyaf extremist group in the southern province of Sulu on Thursday.

Military officials reportedly said that government security forces attacked a group of fighters from the Islamist group, which has been involved in carrying out bombings, kidnappings and assassinations in the country, prompting a gun battle that claimed the life of one soldier in Kagay village in Sulu, where the militant group has maintained a base for years.

The incident was reportedly followed by another attack close to the scene of the initial battle 10 minutes later, which killed six more soldiers and injured 13, Associated Press reported, citing military spokesman Lt. Col. Ramon Zagala.

Zagala also reportedly said that the remaining troops are still in the area, where the operation has been taking place, while those injured have been evacuated to a nearby hospital for treatment. The identities of those killed in the attack are yet to be revealed, Zagala said, adding that there was no information of any militant being killed in the operation so far.

“We (have) yet to inform the families of our members who were killed and wounded during the encounters in Sulu. Rest assured that they are being well taken care of,” Zagala said, according to GMA News, a local news website.

Abu Sayyaf, which has been listed as a terrorist group by the U.S. Department of State, was established in the early 1990s in Basilan province, about 100 miles northeast of Sulu.

Philippine army troops had recently captured some militants from the terrorist group, which included the arrest of Khair Mundos, a top Filipino commander who is on the U.S. most-wanted terrorists list. Two other militants from the group, Jimmy Nurilla and Bakrin Haris, were captured earlier this week, during a raid in the port city of Zamboanga, where the militant group has reportedly conducted many attacks.

The latest attack linked to the Abu Sayyaf group happened on Monday when at least four gunmen reportedly raided a fish-farm in Kunak, about 37 miles from Lahad Datu, in the east of Sabah, Malaysia, and kidnapped a worker and his owner.