A boat carrying 300 kg of heroin was seized yesterday during a joint operation conducted by the State Intelligence and the Sri Lanka Navy in the southern seas. The arrests were made following a tip-off received by the Police Narcotics Bureau.  Defence Secretary Kamal Gunaratne and Navy Commander Vice Admiral Nishantha Ulugetenna inspected the contraband of the seized narcotics. Pix by Damith Wickramasinghe