The two combatants in the war in Sri Lanka were never short of firepower. The Sri Lankan Army and the Tamil Tigers had accumulated stocks of munitions, the former helped by China and the latter by devoted agents tapping into the global market of Russian-made weapons.

Both sides ended up with similar weapons, such as 81mm and 82mm mortars and heavy and light artillery pieces. All the signs are that they were used on a huge scale, particularly by the Sri Lankan Army.

Little care seems to have been given to the Geneva Conventions. Under Article 15 of Part II of the 1949 Geneva Convention, parties to a war are obliged “to shelter civilian personnel not taking part in the hostilities from the effects of war”.

Mortars cannot be fired with accuracy. If they are air-burst, the rockets can be equipped with a proximity fuse that is sensitive to the density of the ground. If the ground is soft the mortar rocket can be detonated at a higher altitude, anything up to 200ft (61m), according to Charles Heyman, the editor of Armed Forces of the United Kingdom. His view, after examining the photographs, was that air-burst mortars had been used.

Colin King, a weapons expert with Jane’s publications, said he thought it was more likely that the mortars had ground impact fuses. “They descend vertically and explode horizontally, like World War One mortars,” he said.

The most common mortars are 82mm rounds, which can be lethal over 10 to 20 metres. A civilian within a 50-metre range could easily be caught by shrapnel.

Will Hartley, the editor of Jane’s Terrorism and Insurgency Centre, said that the Tamil Tigers used 11 merchant ships to deliver weapons. “They got arms from Bulgaria, Ukraine, Cyprus, Thailand and Croatia and other countries,” he said.

The inventory of arms posed a challenge to the Government but China’s assistance resolved that problem.

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