LONDON - Five British troops were killed Saturday in a helicopter crash in southern Afghanistan in what appeared to be a "tragic accident", the Ministry of Defence in London said.
The Lynx helicopter crashed during a routine flight in Kandahar province killing three members of the Army Air Corps, a member of the Royal Air Force and an army reservist with military intelligence, the MoD said.
It is the largest single loss of life for the NATO-led International Security Assistance Force (ISAF) since a US helicopter crashed in December after being hit in a Taliban insurgent attack.
Taliban militants said their fighters had shot down the British helicopter, although the insurgent group often makes erroneous claims of responsibility.
"It is with great sadness that we must confirm that five UK service personnel have been killed in this incident which, at this early stage, would appear to have been a tragic accident," said Major General Richard Felton of the British armed forces' joint helicopter command.
"Events like this, whilst mercifully rare, remind us of the risks our personnel face in their work in Afghanistan as we approach the conclusion of the combat mission later this year.
"Our thoughts are with the families and loved ones of those who have lost their lives."
The loss, which comes just months before the US-led operation in Afghanistan comes to an end after 13 years, brings the total number of British fatalities to 453.
Prime Minister David Cameron said his "heart goes out to the families and friends of those killed in this terrible tragedy".
Every death was a source of "deep sadness", he said, adding: "I cannot pay high enough tribute to each and every one of them for the job that they do and the sacrifices that they make."
- 'A technical fault' -
ISAF had earlier confirmed the crash and said it was "reviewing the circumstances to determine more facts".
Local officials in southern Afghanistan told AFP the helicopter came down in volatile Kandahar and was not attacked by militants.
"A helicopter belonging to NATO troops has crashed in Takhta Pul, Kandahar province," said Zia Durrani, the provincial police spokesman.
"It was doing military exercises and crashed as a result of technical fault."
The Taliban said on a recognised Twitter account that it had targeted the helicopter and the "wreckage caught fire as it smashed onto the ground, killing all invaders onboard".
Six US troops were killed in the December attack when a Blackhawk chopper went down in the southern province of Zabul.
US officers initially blamed a mechanical failure, but said the crew may have then come under fire. Officials later said that Taliban militants brought down the aircraft.
Aircraft crashes have been a regular risk for the ISAF mission in Afghanistan, with troops relying heavily on air transport to battle the Taliban insurgency across the south and east of the country.
NATO troop movements have fallen sharply over the last year, as all combat forces prepare to pull out by the end of December.
From a peak of 150,000 in 2012, about 51,000 international troops are now in Afghanistan, 33,500 of them from the United States and around 5,200 from Britain.
British forces use Westland Lynx helicopters for a wide variety of operations, including transport and supply.
Five service personnel were killed when one of the aircraft was shot down by a surface-to-air missile in Basra City in Iraq in May 2006.
The deadliest incident for British troops in Afghanistan was in September 2006, when all 14 personnel on board a Nimrod surveillance aircraft were killed in a crash caused by a leaking fuel pipe.
Since 2001, a total of 3,436 members of the international military mission have died in Afghanistan, according to the independent icasualties website.
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