FIVE NATO TROOPS died in a British helicopter crash today in southern Afghanistan, authorities said, the single deadliest day this year for foreign forces as they prepare to withdraw from the country.

The cause of the helicopter crash was not immediately known.

Kandahar provincial police spokesman Zia Durrani said the helicopter went down in the province’s Takhta Pul district in the southeast, about 50 kilometers from the Pakistani border.

He said five international troops were killed but did not know what caused the crash.

Sky News is reporting that all five soldiers are British.

The coalition said it was investigating the circumstances of the crash but said it had no reports of enemy activity in the area. The UK’s Defense Ministry confirmed that the helicopter was British, but could not confirm the nationalities of the dead.

A Taliban spokesman claimed in a text message to journalists that the insurgents shot down the aircraft.

“Today, the mujahedeen hit the foreign forces’ helicopter with a rocket, and 12 soldiers on board were killed,” spokesman Qari Yousef Ahmadi said. The insurgents frequently exaggerate death tolls in their attacks and falsely have claimed responsibility for incidents before.

Today’s deaths bring to seven the number of international troops killed this month. So far this year, 23 have been killed, according to an Associated Press count, a far lower number than previous years as international troops have pulled back to allowed Afghan security forces to take the lead in security operations.

The NATO force is preparing to withdraw its troops from Afghanistan at the end of this year, 13 years after the US-led invasion to topple the Taliban’s hard-line Islamic regime for sheltering Osama bin Laden and other al-Qaida leaders.

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