MANILA - The military should prepare for retaliation after it killed Omar Maute and Isnilon Hapilon, top leaders of the ISIS-inspired militants that laid siege in Marawi City, an analyst said Monday.

• READ: Terrorists Isnilon Hapilon, Omar Maute killed in Marawi battle

Hapilon and Maute's death during a military operation in the Islamic city would create a "step back" to the ISIS-linked organizations in the Philippines, especially those responsible for the months-long clashes in Marawi City, said Professor Rommel Banlaoi of the Philippine Institute for Peace, Violence, and Terrorism.

"The death of the 2 leaders shall not make our law enforcements complacent because we have seen many times in the past that the death of the 2 leaders will not stop these terrorist organizations from wrecking terrorist havoc," he told ANC.

The military, he added, has to prepare for "possible retaliatory attacks" considering that Hapilon’s second in command, Furuji Indama, now heads a battalion of a separate ISIS caliphate in East Asia.

"The death of Hapilon and Maute will just send our law enforcement authorities a new form of battle against terrorist threats. Their deaths will not end our fight to end terrorism in the country," said Banlaoi.

"Our authorities should intensify their intelligence-gathering on the issue in order to prevent them from carrying their benevolent intentions," he added.

Defense Secretary Delfin Lorenzana Hapilon and Maute were killed in a military assault, with the help of a hostage who divulged the terrorists' whereabouts.

Military is still chasing a certain Dr. Mahmud, a Malaysian terrorist who could still be hiding in a building in Marawi's battle area.

"We may be announcing the cessation of hostilities in Marawi within this week. We will assess the entire Mindanao if there is a need to recommend to the President to lift martial law [in Mindanao]," said Lorenzana.