Among the bodies recovered inside the house, there were three men, three women and six children.
Three more bodies of men suspected to be suicide bombers were also found outside the house.
Police said there were no casualties of armed forces personnel.
The Police suspect a suicide bomber had triggered the explosion.
Police spokesman Ruwan Gunasekera said that the Police and the Special Task Force (STF) received a tip from a police constable who was on traffic duty about a house with a group of suspicious people.
“When the STF tried to enter the house, shots were fired from the house towards the STF commandos followed by an explosion inside the house,” he said.
A severely injured woman and a child were found inside the house and were hospitalized by the armed forces.
Search operations are still going on.
An indefinite curfew was clamped in the Kalmunai, Chawalakade and Sammanthurai Police areas after a gun battle ensued between STF personnel and an armed group in the Sainthamaruthu area in Kalmunai.
A stock of more than 150 gelignite sticks, IS uniform, a large stock of steel pellets, a drone, a suspicious van and a laptop were also recovered during the search operation in Samanthurai.
He said the objects were detected based on information received by the State Intelligence Service.
Meanwhile, the police curfew in the other parts of the country was effective from 10 pm on Friday to 4 am on Saturday.
Police spokesman Ruwan Gunasekara said 80 suspects had been arrested so far on suspicion of having links with the recent terror attacks.