Bomb squad personnel, commandos and police personnel searched the premises of the 'Naharolgi Thoudang' and 'Hueiyen Lanpao' after cordoning off the area, the sources said.
Nothing, however, was found and the police were investigating where the call came from, they said.
Home Minister Gaikhangam, who was informed about the development, instructed the police to look into the matter.
The All Manipur Working Journalists' Union (AMWJU) and editors of local dailies yesterday held a meeting condemning the threat by a particular militant outfit to journalists and editors if their press statements were not published in verbatim.
"We have decided not to publish any statement of militant outfit which is not newsworthy and we will not work under any pressure from any quarter," an AMWJU spokesman said.