A BRITISH helicopter has crashed in southern Afghanistan, killing five Nato troops in the bloodiest day this year for foreign forces in the conflict.
The Taliban claimed to have shot down the helicopter in Kandahar but military sources said enemy action was not believed to be involved.
The International Security Assistance Force said the troops died in the crash in southern Afghanistan on Saturday morning.
A statement said: "ISAF is still in the process of reviewing the circumstances to determine more facts. Our thoughts and prayers go out to the family and friends."
The nationality of the troops has not been officially confirmed but they are all thought to be British. They will not be named until their families have been informed.
A spokesman for the Ministry of Defence said: "We can confirm that a UK helicopter crashed in southern Afghanistan today.
"The incident is under investigation and it would be inappropriate to comment further until families have been notified."
The worst air disaster for British forces in Afghanistan was the crash of a Nimrod aircraft in September 2006, when 14 crew members died.
If confirmed, the latest casualties will bring the total number of British military personnel to have died in Afghanistan to 553 since the conflict began in 2001.
Zia Durrani , a spokesman for Kandahar police, said the aircraft went down in the Takhta Pul district, about 31 miles from the Pakistani border, but did not know the cause of the crash.
A Taliban spokesman sent a text message to journalists claiming that the insurgents shot down the helicopter.
"Today, the mujahedeen hit the foreign forces' helicopter with a rocket, and 12 soldiers on board were killed," Qari Yousef Ahmadi said.
The insurgents frequently exaggerate death tolls in their attacks and have falsely claimed responsibility for other attacks.
Seven troops from the international forces have been killed in Afghanistan this month.
Nato is preparing to withdraw from Afghanistan at the end of 2014 and transfer responsibility for the ongoing struggle against the Taliban to the Afghan army and police.
Violence has increased in the country as the withdrawal approaches and through the period leading to the elections on 5 April. Preliminary results of the vote were due later on Saturday.
Two Americans killed in a shooting at a hospital in Kabul earlier this week have been named as Jon Gabel, a health clinic administrator and his visiting father, Gary.
The vice chancellor of Kabul University, Mohammad Hadi Hadayati, said that Mr Gabel's wife was wounded in the attack on Thursday, when an Afghan police security guard opened fire as the family entered the grounds of Cure International Hospital.
The family was visiting pediatrician Dr Jerry Umanos, from Chicago, who was also killed.
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