Thomas Maresca

Special for USA TODAY

Violence erupted for a third day in the restive southern province of Mindanao on Thursday, as the Philippine army sent in tanks and launched airstrikes against members of the Islamic State-linked Maute group in the city of Marawi.

Lt. Col. Jo-ar Herrera, a spokesperson for the armed forces, told reporters the army used “very precise, surgical airstrikes,” from attack helicopters to try and flush out the remaining 30 to 40 members of the terrorist group that clashed with government forces and besieged the city, leaving at least 21 dead.

The White House condemned the violence by militants linked to the Islamic State, also known as ISIS. “Cowardly terrorists killed Philippine law enforcement officials and endangered the lives of innocent citizens,” the White House said in a statement Thursday. The U.S. vowed to provide “support and assistance to Philippine counterterrorism efforts” as a “proud ally of the Philippines.”

The fighting started Tuesday as government forces raided the safe house of Isnilon Hapilon, a leader of the extremist group Abu Sayyaf and believed to be a key figure for the Islamic State in Southeast Asia. Hapilon is on the FBI’s most wanted list.

The raid, which failed to capture Hapilon, set off a violent backlash by groups of militants who swept through the streets. Reports from various officials claimed that a policeman was beheaded, a Catholic priest and several worshippers were taken hostage, ISIS flags were raised throughout the city and buildings were burned.

Hapilon’s whereabouts are still unknown.

President Rodrigo Duterte on Tuesday declared martial law on the island of Mindanao and said Wednesday that he may extend it to the rest of the country.

"Government must put an end to this,” Duterte told reporters Wednesday after returning from an official visit to Russia. “I cannot gamble with ISIS because they are everywhere and you know what is happening or you must be very aware of what is happening in the Middle East."

The controversial president invoked the legacy of former dictator Ferdinand Marcos, who imposed martial law on the country in 1972 for almost 10 years — a period marked by torture, extrajudicial killings, human rights abuses, graft and corruption.

“It will not be any different from what the President, Marcos did,” said Duterte in a Facebook Live video before heading back to Manila from Russia. “I'd be harsh.”

Human rights groups were quick to criticize the comparison.

“For Filipinos who lived through martial law under Ferdinand Marcos, Duterte’s casual reference to the late dictator should be especially alarming,” said James Ross, legal and policy director for Human Rights Watch.

“The coming days and weeks will see if the Philippine Congress and courts are up to the task of keeping a wildly abusive president in check,” Ross said. “Since Duterte took office nearly a year ago, they haven’t been.”

Duterte still enjoys supermajority support in Congress and there have been no indications that lawmakers intend to revoke the order.

One of Duterte’s most outspoken critics, Sen. Antonio Trillanes IV, told reporters Wednesday that Duterte is laying the groundwork for nationwide military rule.

“If you give Duterte some leeway, it will be the entire Philippines next,” Trillanes said, according to Philippine news site Rappler.com. “He is already training, conditioning the minds of the people that martial law is okay. It's not — it's an extreme option. The requisites for that (are) invasion or rebellion.”

Analysts say the threat from ISIS-linked groups in the Philippines is going to remain a primary challenge for Duterte. Richard Javad Heydarian, assistant professor of political science at De La Salle University in Manila and author of a forthcoming book on Durterte, said the pressure is on the president to address the crisis of extremist violence that has long plagued his home province of Mindanao.

“As the first president from Mindanao, public expectations have been and continue to be high,” Heydarian said. “Counterterrorism will likely dominate his agenda in the short to medium run, and this will likely nudge him to solicit assistance from tried and tested allies like America.”

Since taking office, Duterte has pushed repeatedly for closer relations with China while at the same time limiting the longstanding military relationship with the U.S., scaling back joint military exercises, and canceling plans for joint maritime patrols.

But Rohan Gunaratna, professor of security studies at the S. Rajaratnam School of International Studies, Nanyang Technology University in Singapore, said Duterte will need the assistance of the U.S. in fighting an ISIS threat.

“To fight the current wave of (ISIS) in the Philippines, President Duterte will need access to high-grade intelligence, which the Americans have, and access to superior-firepower weaponry,” said Gunaratna. “President Duterte has shifted towards China for economic reasons. But in terms of managing security threats, he will need the blessings and the cooperation of the Americans.”

Gunaratna said that martial law itself will not help in the fight against terrorism, but it sends a message.

“Martial law is symbolic,” he said. “Declaring martial law demonstrates that he's serious. Identifying (ISIS) as the threat shows that he has identified the enemy.”

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