MANILA (UPDATE) - Supporters of the National Democratic Front (NDF) clashed with Muslims in Mendiola on Thursday, the day of the signing of the Comprehensive Agreement on the Bangsamoro (CAB) in Malacanang.

Around 100 militant activists, composed mostly of youth protesters, emerged from Recto Avenue and trooped to Mendiola where Muslims were holding prayers and were reading the Koran.

The Muslims, apparently insulted by the protesters' chants, attacked the protesters. There was no large police presence in the area when the clash erupted.

The protesters were forced to step back after they were outnumbered by the Muslims who were in the area to celebrate the historic signing.

"Kailangan mapigilan ang mga gumugulo. Respeto naman po sa ating programa," said a Muslim imam interviewed by dzMM.

The tension eventually died down after the arrival of police personnel. As of posting, the militant activists have already left the area.

The Communist Party of the Philippines and its allied organizations in the National Democratic Front are set to celebrate the 45th founding anniversary of the New People's Army on March 29. The group has also been protesting the arrest of its top leaders, couple Benito and Wilma Tiamzon.

While the government's talks with the Moro Islamic Liberation Front (MILF) have been successful so far, its negotiations with the communist rebels remain stalled after collapsing last year.

Following 17 years of negotiations, MILF leaders will sign the peace deal in exchange for control of a planned autonomous region in the impoverished south.

Moro rebels have been battling for more than four decades for independence or autonomy in the southern region of Mindanao, which they regard as their ancestral homeland.

Tens of thousands of people have died in the conflict, while Mindanao has become one of the poorest and most corrupt regions in the Philippines.

The MILF, which the military estimates has about 10,000 fighters, is the biggest remaining rebel group yet to sign a peace accord.

President Benigno Aquino III and MILF chairman Murad Ebrahim will oversee the signing of the peace deal during a ceremony at the presidential palace in Manila.

The pact will see the two sides become partners in seeking to implement the peace deal.

The MILF chiefs would eventually order their men to give up their arms while themselves becoming politicians leading the autonomous region.

The autonomous region would comprise about 10 percent of the Philippines' territory, have its own police force, a regional parliament and power to levy taxes. The national government would retain control over defense.

Nevertheless, the MILF, the government and independent observers warn a lasting peace is far from guaranteed, with many obstacles still to be overcome before the middle of 2016 -- a crucial deadline as that is when Aquino will step down. – report from Noel Alamar dzMM; with Agence France-Presse