A NATO airstrike on Wednesday mistakenly hit an Afghan army unit in southern Afghanistan, killing five soldiers, a Defence Ministry spokesman said, DPA reported
The soldiers were conducting an anti-insurgent operation in the Andar district of Ghazni province when a plane of the NATO-led International Security Assistance Force (ISAF) targeted the unit, killing five soldiers and injuring two, General Zahir Azimi said.
"It is not the first time," he said. "It has happened several times in the past, but we hope that this should be the last time."
ISAF spokesman General Joseph Blotz said a lack of coordination between foreign troops and Afghan soldiers on the ground could have been the reason for the mistake.
"What we know so far is, yes, indeed, ANA [Afghan National Army] troops have been attacked by the ISAF," he said. "I do clearly regret what has happened."
A joint investigation by Afghan and NATO officials was under way, Blotz said.
More than 130,000 foreign troops are currently based in Afghanistan, fighting alongside Afghan forces against the Taliban.
The international troops also have been training Afghan police and army forces before handing over responsibility for the country's security to them.
In a separate operation, NATO aircraft targeted two groups of Taliban militants late Tuesday in the southern province of Kandahar, killing six insurgents, the provincial government said.
The suspected militants were trying to plant homemade bombs on two dirt roads in the Panjwayi district when they were targeted by the planes, it said.
Also Tuesday, four Afghan police officers were killed when their vehicle was hit by a roadside bomb in the Baraki Barak district of the central province of Logar, 60 kilometres south of Kabul, the Interior Ministry said.
Taliban militants rely heavily on the use of roadside bombs as part of their insurgency, now in its ninth year. Such bombings doubled in the first four months of this year compared with the same period of 2009, according to the United Nations.