Philippine President Rodrigo Duterte said on Wednesday he will deal harshly with terrorism and that martial law on the island of Mindanao would remain in place for a year if necessary.

Duterte cut short a visit to Russia and placed the southern island of Mindanao under martial rule on Tuesday after a fierce bout of fighting erupted during a raid by security forces at a hideout of Islamic State-linked militants.

"To my countrymen who have experienced martial law. It would not be any different from what President Marcos did. I’d be harsh,” Duterte said in an interview with his assistant communications secretary while onboard a flight back to Manila.

"If it would take a year to do it then we'll do it. If it's over with a month, then I'd be happy. To my countrymen, do not be too scared. I'm going home. I will deal with the problem once I arrive," said Duterte, a native of Mindanao.

Two soldiers and a policeman were killed and 12 people wounded amid chaos in Marawi, a predominantly Muslim city of about 200,000 people, where members of the Maute militant group took control of buildings and set fire to a school, a church and a detention facility.

The Philippines endured a decade of martial law under the late dictator Ferdinand Marcos from the early 1970s and memories of campaigns to restore democracy and protect human rights are fresh in the minds of many people.

The military said it was optimistic they could end the conflict sooner rather than later.

"The intent of these security forces, the Armed Forces of the Philippines, is to conclude this rapidly so that we can restore normalcy in that area," military spokesperson Edgar Arevalo said in an interview with news channel ANC.

The purpose of Tuesday's raid was to capture Isnilon Hapilon, a leader of the Abu Sayyaf group which is notorious for piracy and for kidnapping and beheading Westerners. The U.S. State Department has offered a bounty of up to $5 million for Hapilon's arrest.

The Maute and Abu Sayyaf militant groups have pledged allegiance to Islamic State, also known as ISIS, and have proved fierce opponents for the military as Duterte seeks to crush extremists and prevent radical Islamist ideology from spreading in the Philippines.

Duterte has warned repeatedly that Mindanao, an impoverished, restive region the size of South Korea, was at risk of "contamination" by Islamic State fighters driven out of Iraq and Syria.

Arevalo insisted there is no ISIS in the Philippines.

"This so-called group who are posing to be ISIS, they are merely courting the acclamation of ISIS which until now they haven’t received, that’s why they continue with their atrocities," Arevalo said.