MANILA, Jan. 24 (Xinhua) -- Three soldiers were wounded on Thursday in a fresh fighting between the government troops and remnants of a local Maute group fighters in southern Philippines Lanao del Sur province.

Col. Romeo Brawner of the Philippine 103rd Infantry Brigade said the firefight broke out at around 8:00 a.m. local time when troops encountered 24 members of the so-called "Maute ISIS" remnants, a potent insurgent group that attacked Marawi City in southern Philippines in 2017.

"Firefight is still on going as of this posting," Brawner said.

Brawner said the Maute fighters also suffered "an undetermined number of casualties."

"Casualties were immediately extracted from encounter site for medical treatment," Brawner added.

Maj. Gen. Roseller Murillo, 1st Infantry Division and Joint Task Force Zampelan commander, said Thursday's "armed encounter is the result of our relentless campaign against Maute remnants and Abu Dar group."

Abu Dar is allegedly the new leader of the Maute group. He has a 6 million pesos (roughly 113,697 U.S. dollars) bounty.

Lanao del Sur province on Mindanao island is under martial rule. Philippine President Rodrigo Duterte imposed martial law in the entire island since Maute group attacked Marawi City in May 2017.

Security forces ultimately cleared the city and eliminated much of the terrorist leadership, including the Maute brothers who founded the militant group called Islamic State Ranao.

At least 1,200 people, including soldiers and terrorists, were killed in the Marawi siege that also flattened the city's business center. The government is still in the process of rebuilding the city's central business district.

Philippine Congress has granted Duterte's three requests for martial law extension to quell the rebellion in the southern region. Martial law remains in the region until Dec. 31.