The complainant was Dilanthe Withanage, BJP secretary, who is contesting from Gampaha at the general election.
After lodging the complaint, he told the media that the facebook page of the Sri Lankan ISIS fighter who had been killing in Syria had hinted that Gnanasara Thera should be killed.
The man, Mohamed Muhadeen Sarnas Nilam alias Nilabdeen, was the former principal of an international school and a karate champion.
Withanage added that the ISIS was gathering information about BJP activists.