MANILA: The top leaders behind the months-long war in Marawi have been killed, Philippines Defence Secretary Delfin Lorenzana confirmed Monday.

Details on the deaths of the two leaders killed in clashes, Isnilon Hapilon and Omar Maute, were not immediately given. The two had pledged allegiance to the Islamic State (IS) terror group.

Universiti Malaya professor-turned-militant Dr Mahmud Ahmad, however, is believed to be still alive.

Dr Mahmud was among the key planners of the May 23 Marawi attack, together with Hapilon and Omar, for the creation of a caliphate in South-East Asia.

The conflict between Philippine government forces and armed groups started May 23, when authorities tried to arrest Hapilon.

The armed groups were also supposed to establish a wilayat or an IS province in Marawi reported by Philippine Daily Inquirer/Asia News Network.