Police and military entered the organisation's main mosque in Kattankudy, in eastern Sri Lanka.
The bodies of 15 people, including six children, have been discovered at the site of a fierce overnight battle on the east coast of Sri Lanka.
Police say three men set off explosives inside what was believed to a terror group' safe house.
Senior Lecturer in Sociology at Deakin University and expert in the study of extremism and hate Matteo Vergani tells SBS Italian what are the consequences of the largest attack allegedely carried out by the Islamic State outside Syria and Iraq.