The Eastern Naval Command is seriously considering the reintroduction of defensive measures in Trincomalee Harbour area abandoned after the Cease-Fire Agreement in 2002. This includes depth-charges dropped randomly inside the Trincomalee Inner-Harbour throughout the day and night.
The measures come after the May 10th sinking of A-520 logistics and supplies vessel in the Trincomalee Inner Harbour area. The ship is yet to be salvaged after a powerful explosion. Senior officers told DefenceWire that a lack of debris seems to indicate the attack may have been launched by a team of frogmen/women. However, a human torpedo attack is not completely ruled out. We are aware of a transferring of Fiber Reinforced Plastic (FRP) technology from North Korea to the LTTE many years before (LTTE Midget Submarines).
Effective defenses against both modus operandi is crucial considering that Pearl Cruise II often docks in the same harbour. In 2006, Sea Tigers made an abortive bid to destroy the vessel in open seas. On a previous suicide boat attack, the Tigers destroyed one of two Australian-built troop transport Catamarans inside the Inner Harbour.
Immediately after the May 10th attack, the Navy imposed an unofficial ban on fishing vessels near the harbour mouth. Fishermen from nearby fishing villages, particularly in Kinniya and Mutur have been asked to register themselves for security reasons. Currently, under the official restrictions imposed after the 10th, fishing is allowed outside of the inner harbour area from 2am to 6pm (the latest attack took place at 2.15am).
A Closed Circuit Re-breather (CCR). Did the Tigers receive them in arms shipments in February and March this year?The depth-charges are a deterrence against similar attacks in future, but not a complete solution to the problem. The Navy also limited underwater surveillance and motion-detection systems at its disposal. These have not been able to prevent the May 10th attack. The Navy may have to deploy its own Combat Divers from the Special Boat Squadron in future. This, however, will undoubtedly endanger the lives of valuable men.
The reality is that no complete solution is available against frogmen. Although the Navy has new marine radars, it is handicapped in the area of underwater surveillance. The Sea Tigers have perfected the art of maintaining radio silence and hardly ever give-out any clues over their communications.
Each attack team has the ability to operate independently thanks to accurate intelligence, training and mission-briefing. Captured LTTE frogmen have confessed of being trained overseas. These factors make, specially the Underwater Demolition (UDT) and Suicide Teams extremely difficult to detect.
However, prior to the cease-fire, depth-charges were used regularly in the Inner Harbour area as an effective deterrence. The charges were used after a gunboat was destroyed by a female suicide-bomber in 1995. The charges can send a diver into shock or even kill the diver, but only if it detonates closer to him/her.
The Navy therefore used fast boats to drop depth-charges every few minutes at various points of the Inner-Harbour. A large number of marine creatures were killed and washed ashore during the process while shaking Naval barracks and officer quarters around the Inner Harbour with each explosion.