Duterte, who is known internationally for waging a war on drugs that has claimed thousands of lives, had said on many occasions since becoming president a year ago that he was prepared to declare martial law nationally as well as in Mindanao.
Duterte made a decision to cut short his visit to Moscow, where he had been scheduled to meet Russian President Vladimir Putin and Prime Minister Dmitry Medvedev.
Two soldiers and a police officer have been killed, Defense Secretary Delfin Lorenzana said.
The Philippines military has been running a two-front anti-terror campaign in Mindanao - one against the Abu Sayyaf Group (ASG) based in Western Mindanao in the islands of Sulu and Basilan, and another against the Maute and its Abu Sayyaf allies in the Lanao provinces in Northern Mindanao.
Officials said the gunmen occupied the city hall, a hospital and a jail and burned several houses in a daring attack. "We can't let a madman with nuclear weapons let on the loose like that". I said I'd be harsh.
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Iraq and Iran posed the main obstacles to OPEC in reaching a deal for its last output cutting decision in December. Saudi Arabia and non-OPEC Russia have been pushing to extend the cuts by nine months until March 2018.
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Wallace fell out of contention for the overall tournament with a 42 on his first nine holes, but Sagoo backed up as well. Penn State and Golfstat number one ranked USC were the only teams with two or more golfers in the top-10.
Duterte arrived in Moscow on Tuesday for a four-day official visit, but was forced to cut short his trip as fighting broke out in the southern Philippine region of Mindanao. But as the Washington Postpoints out, people in the Philippines still remember the last time a President declared martial law: "In 1972, then-President Ferdinand Marcos declared martial law to ensure that he would remain in power beyond the end of his second term the following year". "When it comes to the military sphere, the current situation in the world is reaching a critical state, and I can't rule out military alliances", Duterte told Russian news agencies before his visit.
Security forces in the mostly Christian Philippines have battled Muslim separatists for decades and peace efforts have led to a reduction in clashes with main groups.
The fighting erupted on Tuesday afternoon when the Maute group opened fire on personnel from the military's 103rd Brigade, a police director said.
The post-Marcos constitution imposed safeguards on martial law, including the requirement for congress to approve its imposition and extension.
"I have to express our condolences (for the) loss of lives of your people (that) happened because of a terrible terrorist attack".
Human rights groups have expressed fears martial law powers could further embolden Mr Duterte, whom they have accused of allowing extrajudicial killings of thousands of drug suspects in a crackdown on illegal drugs.
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This second goal was scored by Philippe Coutinho from a direct free-kick, his third goal of this type this season. He has, however, indicated that his future will be discussed at a club board meeting after the FA Cup Final.
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Qualifying was marred by a frightening crash that sent Sebastien Bourdais to the hospital complaining of pain in his right leg. You'll hear commentators talk more about the average speed of those four laps, expressed in miles per hour .