Three British soldiers have been seriously injured in a "friendly-fire" incident in Afghanistan.

Six others were hurt when a British Apache helicopter shot at troops from the Second Battalion the Parachute Regiment.

The Ministry of Defence says they were mistaken for the enemy during a fierce battle with the Taliban in Helmand province.

The Battalion has already lost seven men during this tour.

One of the more seriously injured has been flown back to the UK but is in a stable condition.

Two others remain at Camp Bastion medical centre where they were being kept for observation.

The six others have been discharged and have returned to their duties.

An MoD spokesman said: "A routine British patrol requested fire support from a British Apache when they encountered enemy forces near Forward Operating Base Gibraltar.

"After successfully engaging one enemy position, the Apache fired upon another position which the crew believed to be held by enemy forces.

"However, in the confusion of a rapidly changing situation and in what is a challenging environment, it would appear that friendly forces were mistaken for the enemy and as a result three members of the patrol were seriously wounded and six more were classified as walking wounded.

"The seriously wounded personnel were moved by helicopter to Camp Bastion medical facilities.

"An investigation is under way into how the incident occurred and it would be inappropriate to comment until that investigation is complete."

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