KABUL, Afghanistan -- A British helicopter crashed in southern Afghanistan on Saturday, killing five NATO troops in the single deadliest day this year for foreign forces as they prepare to withdraw from the country, officials said.
The British defense ministry confirmed that all five of the dead were British. Maj. Gen. Richard Felton, commander of the Joint Helicopter Command, said the crash appeared to be "a tragic accident."
The cause of the helicopter crash was not immediately known. Kandahar provincial police spokesman Zia Durrani said the aircraft went down in the province's Takhta Pul district in the southeast, about 31 miles from the Pakistani border.
The coalition said it was investigating the circumstances of the crash but said it had no reports of enemy activity in the area.
Saturday's crash was one of the deadliest air accidents involving Britain's forces in Afghanistan. In September 2006, a Nimrod surveillance aircraft exploded in mid-air while supporting NATO ground operations near Kandahar, killing all 14 servicemen on board.
A Taliban spokesman claimed in a text message to journalists Saturday 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," spokesman Qari Yousef Ahmadi said. The insurgents frequently exaggerate death tolls in their attacks and falsely have claimed responsibility for incidents before.
The last deadliest day for coalition forces was Dec. 17, 2013, when a helicopter crash killed six U.S. service members.
Saturday'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 allow 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 U.S.-led invasion to topple the Taliban's hard-line Islamic regime for sheltering Osama bin Laden and other al-Qaida leaders.
Violence has increased in Afghanistan ahead of the NATO withdrawal and also in the weeks leading up to the country's April 5 election. Preliminary results of the vote were announced Saturday and indicated a runoff would be held in several weeks between top vote-getters Abdullah Abdullah, a former foreign minister, and Ashraf Ghani Ahmadzai, an ex-finance minister.
Late Saturday afternoon, a suicide bomber targeting a police vehicle detonated his explosives-laden rickshaw in the eastern province of Ghazni, killing two police officers and three civilians, said provincial deputy police chief Col. Asadullah Ensafi. Seven others were wounded in the attack.