Idukki and its adjoining areas experienced mild tremors on Sunday afternoon. The tremors measured 1.5 on the Richter Scale. The epicentre of the tremor was at Karinkunnam near Pala and Moolamattam, the Kerala State Electricity Board (KSEB) sources said. The KSEB Dam Safety Cell in Idukki could not detect the exact magnitude of shock as its analog system is outdated. However, no casualties were reported from anywhere.