Police spokesman SP Ajith Rohana said that two women and a 12 year old child were killed when they were inside their house.
All three were pronounced dead on admission to hospital.
Meanwhile the department of meteorology said that thundershowers will develop at several places in most parts of the island during the afternoon or evening tomorrow.
There may be temporary localized fairly strong winds together with thundershowers.
“The general public is kindly requested to take adequate precautions to minimize the damages caused by lightning activities,” the department of meteorology said.