Manila, December 05, SPA -- Philippines President Gloria Macapagal-Arroyo declared martial law beginning Friday night in the southern province of Maguindanao, where 57 people were killed last week, an army spokesman told CNN Saturday. Army spokesman Lt. Col. Romeo Brawner Jr. said martial law -- under which police can make arrests without a warrant -- went into effect at 9 p.m. Congress would have to approve any extension beyond 60 days. Brawner said the measure was invoked to impose peace on the region after the unrest, which led to troops being mobilized. "Life is to resume normally and martial law is established to prevent new violence, with troops on the ground monitoring any possible violence breakout," he said. "But the civilian government will be running the affairs of the province, not a military governor." --SPA 15:42 LOCAL TIME 12:42 GMT www.spa.gov.sa/725069