A stock of some 300 sharp blades manufactured abroad, was found from the Sembukuliya Tank in Kekirwa on Sunday, security sources said.
Two men engaged in fishing in the tank had noticed a suspicious bag in the tank and informed the police.
The blades ranging between 8 inches to 10 inches had been greased and packed in a water-proof bag. Security sources suspected if this was aimed at committing criminal activities by a person or a group.
No arrests have been made so far over this finding.