http://news.bbc.co.uk/1/hi/uk/7501069.stm :
The Ministry of Defence is trying to find out why an Army helicopter accidentally fired on UK paratroops in southern Afghanistan, wounding nine.
The Apache attack helicopter was called in by ground troops battling with Taleban fighters in Helmand province.
In a second attack, a British position was mistaken for the enemy and three soldiers were seriously hurt.
The incident is the first case of "friendly fire" by British air support on its own forces in Afghanistan.
Six of the wounded have returned to duty. Two are stable in a field hospital. One man was flown back to the UK for treatment.
When you've got eyeball to eyeball, the technology is not going to help you as much as you hoped
Charles Heyman
Armed Forces
Factfile: AH-64 Apache
The soldiers from the 2nd Battalion of the Parachute Regiment - 2 Para - were on a routine foot patrol near the British forward operating base Gibraltar in the Helmand River Valley when they encountered Taleban fighters.
They called in air support from the Army's Apache helicopter, which successfully fired on a Taleban position.
But then in the confusion of what the MoD termed a "rapidly-changing situation", it fired again on another position, which the crew believed was held by the enemy.
An investigation is now under way into the incident. There was no public statement from 2 Para's headquarters in Colchester.
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The BBC's Alastair Leithead in Kabul said air support had a difficult job when Taleban positions were possibly less than 100 metres away from British troops.
He said the tree-lined terrain with high compound walls and deep irrigation ditches presented further difficulties.
Charles Heyman, director of defence suppliers Armed Forces said there was technology to differentiate between friend and foe.
Forward operating base Gibraltar is in the Musa Qala region
However, he said: "It is possible that the Taleban and the British soldiers were very, very close together."
"When you've got eyeball to eyeball, the technology is not going to help you as much as you hoped."
The incident is the first reported occurrence in Afghanistan of "friendly fire" involving only UK troops, although allied forces have previously hit each other's troops during the conflict.
In August last year, three soldiers from 1st Battalion The Royal Anglian Regiment were killed when US fighter planes dropped a 500lb (225kg) bomb on them.
In December 2006, marine Jonathan Wigley died in an apparent attack by the US in Helmand province.
In April 2002, an American F-16 fighter jet dropped a laser-guided 500lb (225kg) bomb near Kandahar, accidentally killing four Canadian soldiers and injuring eight others.