Sri Lankan security forces exchanged fire with suspected ISIS-affiliated terrorists and killed at least four of them in the east of the country, police and the military said Saturday.
Gunmen opened fire on troops when they attempted to storm a house in the town of Kalmunai, military spokesman Sumith Atapattu said. "In our retaliatory fire, two gunmen were killed," he said adding that a civilian caught in the crossfire was also killed.
Police later said clearing operations on Saturday showed a total of four suspected suicide bombers had died during the overnight confrontation.
"We found four bodies of suspected suicide bombers," the police statement said, also confirming one civilian was killed in the crossfire, while three others escaped with injuries.
The joint operation between the police and the army was carried out following a tip off that those responsible for the Easter suicide bombings were holed up in a built up area of Kalmunai, 370 kilometres (230 miles) east of the capital.
There were no casualties among the security forces, the police said.
The clashes came hours after the security forces raided the location where they believe Islamist radicals recorded a video pledge to ISIS leader Abu Bakr al-Baghdadi before carrying out the deadly Easter bombings.
Police said they found an IS flag and uniforms similar to those worn by the eight fighters for the video before they launched Sunday's attacks against three luxury hotels and three churches, killing 253.
"We have found the backdrop the group used to record their video," the police said in an earlier statement on Friday night.
The ISIS had released the video two days after the attack.
Police showed the clothing and the flag on national television, as well as some 150 sticks of dynamite and about 100,000 ball bearings seized from the house.
Security forces armed with emergency powers have stepped up search operations for extremists responsible for the bombings.
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