MANILA, Philippines (AP) -- The Philippine Congress on Saturday overwhelmingly approved the president's appeal for martial law in the south to be extended to the end of the year to help troops quell a two-month siege by Islamic State group-linked militants and stamp out similar extremist plots in the volatile region.
House of Representatives Speaker Pantaleon Alvarez announced that senators and House members voted 261-18 in favor of granting President Rodrigo Duterte's request in a special joint session. The 60-day martial law was to expire late Saturday.
The military chief of staff, Gen. Eduardo Ano, warned during the session that aside from the uprising in Marawi, extremist groups have plotted similar insurrections in other southern cities and that martial law has helped troops stop attacks, including bombings, elsewhere.
"There was an order for them to do their own version of Marawi in other areas, but we were able to stop this because of martial law," Ano told the legislators.
Defense Secretary Delfin Lorenzana played down concerns of military abuses, saying no major human rights violations have been reported since Duterte declared martial law to deal with the Marawi violence, the worst crisis in his yearlong presidency.
Some opponents argued that government forces could deal with the attack in lakeside Marawi, a center of Islamic faith in the southern third of the largely Roman Catholic nation, without resorting to martial law. Others worried that the extension was too long and that the rest of the country may eventually be placed under martial rule.
Left-wing activists opposed to Duterte's declaration rallied outside Congress. Some unfurled protest posters in the plenary hall but were forced out by security officers.
Sen. Risa Hontiveros recalled how civil liberties were curtailed and Congress was padlocked when dictator Ferdinand Marcos imposed martial law in the Philippines in 1972. Marcos was ousted in a "people power" revolt in 1986.
Since the Marawi fighting broke out on May 23, at least 428 militants, 105 soldiers and policemen, and 45 civilians have been killed. Half a million residents have been displaced, according to the military.
During the daylong special session of Congress, a wounded army officer, 1st Lt. Kent Fagyan, told how troops smashed concrete walls of houses and buildings with sledgehammers to advance slowly toward militant positions away from sniper fire. Troops dealt with booby traps and had to wrest back control of Marawi communities room by room, he said, adding that the militants had powerful machine guns, drones and "seemingly unlimited ammunition."
"Inside, you can't eat on time, you can't sleep because you'll be awakened by explosions here and there starting in the morning up to evening for almost 24 hours," Fagyan said.
"On behalf of my colleagues, who are still fighting in Marawi, we thank you for your continued support," he said. "We feel that we're not alone fighting them with the clothes and water that you sent over."
The siege on Marawi started when more than 600 heavily armed fighters, waving Islamic State group-style black flags, stormed into the city, occupying buildings, houses and mosques and taking hostages. Several foreign fighters, including 20 Indonesians and a Malaysian financier known as Mahmud bin Ahmad, joined the insurrection, Duterte said in a letter to Congress this past week.
Duterte wrote in his letter that the leadership of the Marawi siege "largely remains intact despite the considerable decline in the number of rebels fighting in the main battle area." Other radical armed bands "are ready to reinforce Isnilon Hapilon's group or launch diversionary attacks and similar uprisings elsewhere," he said, referring to the leader of the attackers.
Intelligence reports that Hapilon sent funds and ordered allied militants to launch attacks in key cities across the south have been validated, Duterte said.
The attackers' lasting power and large arsenal of weapons have surprised Duterte and his top security officials, who acknowledged they underestimated the combat strength of the militants and their preparations, including the stockpiling of assault firearms in Marawi. Troops long used to fighting insurgents in the jungles have struggled to rout the gunmen from Marawi's dense urban sprawl.
The crisis has sparked alarm that the Islamic State group may be gaining a foothold in Southeast Asia through allied local militants, as it faces major setbacks in Syria and Iraq. The United States and Australia have deployed surveillance planes to Marawi, and China has provided weapons for Filipino troops, including those fighting in the besieged city.