Sri Lankan security forces raided a safe house of Islamic State affiliated militants in the east of the country and killed at least two men in an exchange of fire, the military said Saturday.

Gunmen opened fire on troops when they attempted to storm the house in the town of Kalmunai, 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.