British soldiers riding in a Warrior armoured vehicle accidentally unleashed a barrage of live rounds at Challenger 2 tank during a training exercise blunder.

Troops riding in the heavily-armed 25-tonne military fighter raked the tank with six shots from its armour-piercing 30mm cannon.

The Warrior crew mistook the Challenger 2 for an 'enemy tank' after spotting it through a thermal scope 1,640ft away during an 'intense' live-fire drill.

A team of gunners in the Warrior reportedly performed an 'emergency shoot', firing the armoured vehicle's cannons on fully automatic, emptying the weapon system's magazine.

Fortunately, the Warrior's Rarden cannon was loaded with inert practice rounds instead of high-explosive or armour piercing ones normally used in combat.