In Gujarat, the Security was put on high alert after sound of mysterious explosion reported near the Porbandar Naval Base in Saurashtra. <br/><br/>However, the naval sources termed it the blast of firecrackers. According to tweet from Navy, the blast was not at the Porbandar naval base INS Sardar Patel. Senior police officials and defence sources have started investigation of the incident. According to police, the Guard at the Navy Communication Centre heard a loud sound at 9 am this morning. Top police officials said there is nothing suspicious in or around the naval base till now. <br/><br/>Police sources said that blast may be of firecrackers burst by devotees gathering in a religious fair in nearby areas. AIR correspondent adds that however, the security agencies are not taking any chances and started massive search operation in the area.