AMPATUAN, Philippines: Philippine President Benigno Aquino III on Tuesday promised justice for at least 57 people massacred a year ago in the country's worst election-related violence, amid concerns that politically powerful suspects will be spared. “We will not rest until justice has been served,” Aquino said in a statement on the first anniversary of the killings in southern Maguindanao province, where the justice secretary and the provincial governor led about 3,000 mourners in remembering the victims. One of almost 200 people accused was arrested Tuesday. A team of police and soldiers had arrested Misuari Sinsuat Ampatuan, a member of the Ampatuan clan accused of the massacre in southern Maguindanao province, said national police spokesman Senior Superintendent Agrimero Cruz. “Of the 197 accused, 83 are now under arrest while 112 others are still being hunted,” Cruz added. The main suspect, former Mayor Andal Ampatuan Jr., is accused of ambushing an election convoy and ordering about 200 gunmen to mow down the family and supporters of his political rival. Also among the dead were at least 32 journalists and their staff, the single worst killing of media workers in the world. The journalists in the convoy were accompanying the mostly female relatives of Esmael Mangudadatu in filing his nomination papers for the gubernatorial race in May national elections. Mangudadatu said he believed that women and journalists would not be harmed by his political opponents. Ampatuan Jr., the scion of a powerful political clan, surrendered days after the killings and has pleaded not guilty. His father and brothers also have been charged along with scores of others, mostly government-armed militiamen. Among the 79 suspects in detention, 51 have been arraigned and more than 100 are in hiding. “How the Philippine government handles this case will demonstrate how serious President Aquino is about reining in private armies and curbing human rights violations,” said Sam Zarifi, human rights watchdog Amnesty International's director for Asia-Pacific. Meanwhile, Philippine President Benigno Aquino rejected calls Tuesday to disband state-funded militias like the one allegedly used by a powerful family to carry out the country's worst political massacre. Aquino said the government did not have enough money to rely solely on overstretched regular military and police forces to fight insurgencies, and as such had to use the cheaper alternative of state-backed paramilitary forces.