MANILA, Philippines (AP) " The Philippine Congress voted overwhelmingly Wednesday to approve President Rodrigo Duterte's request to extend martial law in the south by a year after the military warned that terrorist threats continue to lurk despite the defeat of a disastrous pro-Islamic State group siege.

A majority of the Senate and the House of Representatives " with 240 approving and 27 opposing " voted to extend martial law across the Mindanao region through the end of 2018. The vote followed warnings by Defense Secretary Delfin Lorenzana and other officials that pro-IS militants were trying to recover from their defeat in southern Marawi city and were plotting new attacks.

"The rebellion has not stopped, it has just moved to another place," Lorenzana told the senators and House members in a joint session.

Opponents argued that extending martial law in the south is unconstitutional and expressed fears that such a move can be a prelude for Duterte to declare martial law throughout the Philippines.

Sen. Francis Pangilinan, who heads the main opposition Liberal Party, rejected the martial law extension without a clear constitutional basis. "We will be in danger of becoming the monsters that we seek to defeat, those who have no regard for law, order or respect for the constitution," he said.

The Marawi violence left more than 1,100 combatants and noncombatants dead, displaced about half a million people and turned mosque-studded Marawi's central business and residential districts into a smoldering war zone.

The uprising, which began on May 23, prompted Duterte to declare martial law and reinforced fears that the Islamic State group was taking steps to gain a foothold in Asia and elsewhere as it faced battle setbacks in Syria and Iraq.

Some gunmen and commanders managed to escape during the fighting and are now recruiting new militants, while extremist groups in other southern provinces, including the brutal Abu Sayyaf group, continue to pose threats, according to the military.

Filipinos remain hypersensitive to threats to democracy and civil liberties more than three decades after they ousted dictator Ferdinand Marcos in a 1986 "people power" revolt that became a harbinger of change in authoritarian regimes worldwide.