The Special Forces troops, thought to number a dozen, moved in at about 2am, but were fired at by the kidnappers.
The SAS men replied with a barrage of shots from weapons that included C8 SFW carbines fitted with grenade launchers, Heckler & Koch assault rifles, MP5 machine guns, L96A1 sniper rifles and Browning and Sig Sauer handguns.
They are also thought to have carried a supply of Claymore anti-personnel mines and daggers tucked into boots to use in any close-quarters combat.
Local sources said the gang was heavily armed with rocket-propelled grenades and Kalashnikov assault rifles.
By the end of the gun battle, six of the kidnappers had been shot dead, a similar number were captured and the four hostages were freed unharmed in what a senior military source described as a ‘textbook operation’.