It had been a morning of fierce close-quarter combat with incessant fire coming from insurgents in the heart of Taliban country. As the Royal Marines edged their way past the high walls of a compound the section commander, a corporal, fell to the ground with two shots to the groin.

The team had walked into an ambush and Marine Sam Alexander knew that the only chance they had was to fight their way through. He picked up a heavy machine-gun and "traded lead" with the insurgents just 15 metres away. Running out of ammunition, he opened up with his 9mm pistol until that too was spent. The Taliban fighters were forced to withdraw and found themselves being hunted as they ran into other marine units coming in from the flanks.

By his bravery, 26-year-old Marine Alexander saved the life of the shot corporal and also earned vital minutes for the rest of the team from 42 Commando to gain cover. What made his actions even more remarkable was that just a few hours earlier he had been shot in the head, the bullet embedding itself in his helmet. Waving away offers to fall back, he had insisted on continuing with the others as they went through compounds clashing repeatedly with the insurgents.

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Marine Alexander continued with Operation Abii Toorah, Pashtu for Blue Sword, one of a series of missions led by the marines in Helmand which also involved Afghan troops and a Danish contingent with Leopard tanks. The fighting went on with little let-up for the two remaining days, until the Taliban withdrew from the area.

About 600 British and Afghan troops had taken part in an airborne assault supported by B1 bombers and Apache and Cobra helicopter gunships attempting to drive out the Taliban from entrenched positions near Marjah to pave the way for the planned surge which will come with arrival of up to 30,000 extra American troops.

The marines say they came across some of the fiercest resistance they have faced from the insurgents, who were being aided, it is claimed, by Pakistani, Chechen and Arab fighters. According to British forces, "several dozens" of the enemy were killed and more than 100 injured. It was also the first time the Taliban had carried out repeated night attacks, with large bands of fighters attempting to break through the lines while reinforcements arrived from surrounding regions over the days.

According to Afghan and Western officials, while the Americans build up their forces in Helmand and Kandahar, the Taliban are also building up their strength with hundreds of reinforcements arriving from across the Pakistani border.

Several more operations will be undertaken by Afghan and British forces in the next few weeks, with the aim of intercepting the flow of men and weaponry coming through southern Helmand while the Americans are due to carry out missions further east.

100

Number of enemy fighters injured in Operation Abii Toorah, with dozens killed.