KABUL (Agencies) - Afghan President Hamid Karzai on Thursday asked the overall commander of US-led and Nato forces in Afghanistan to explain recent civilian casualties inflicted by foreign troops. Six civilians, including women and children, were killed and 14 wounded, in NATO-led air strikes in eastern Kunar province last Monday. Afghan officials also said a US military raid on April 8 killed four civilians in Khost province. Karzai asked the commander of NATO-coalition forces in Afghanistan for explanations on incidents which recently caused civilian casualties in Khost and Kunar provinces, the presidents office said. The Afghan president met General David McKiernan on Thursday at Karzais palace in Kabul during a security meeting. Expressing deep regrets General McKiernan said, despite continued precaution and efforts by NATO-coalition forces, civilians sustained casualties in Kunar and Khost province, said the statement from the presidency. NATO and US-led troops, in cooperation with Afghan security forces and provincial authorities, investigated each incident and accepted responsibility for them, the statement quoted the top general as saying. NATO-coalition forces apologise to the families of the victims for the civilian casualties, the statement also quoted McKiernan as saying. Provincial authorities said two children, a woman and three men were killed and 14 people wounded in the Watapour district of eastern Kunar province. In Khost, a US army raid killed the wife, two children and a brother of an Afghan army colonel, Afghan officials and witnesses said. Mounting civilian deaths during military operations targeting Taliban and other insurgents is one of the main sources of tension between Afghan authorities and US and NATO-led forces in Afghanistan. Meanwhile, Western forces in Afghanistan acknowledged on Thursday they had killed six civilians in an air strike, just days after apologising for a similar incident that killed five. Civilian deaths caused by foreign troops hunting the Taliban have become a major cause of friction between the Afghan government and its Western backers, and sapped support for the presence of international forces in the country. The NATO-led force in Afghanistan said in a statement on Thursday that it had concluded after a joint investigation with Afghan authorities that six civilians were killed, along with four insurgents, in Mondays air strike in Kunar province. Fourteen civilians were wounded. US-led troops acknowledged last week that they killed five civilians in Khost province. McKiernans NATO-led force had initially said that Mondays raid had been targeting militants in an area where it saw no evidence of a civilian presence. Afghan officials said the attack killed six civilians, including two small children. The number of civilians killed in operations by foreign forces fighting a Taliban-led insurgency has steadily climbed, reaching hundreds last year, according to human right groups and the Afghan government. Western commanders have lately acknowledged that killing civilians-often because of an over-reliance on air power-has cost their troops vital support among ordinary Afghans. Commanders say they are now taking new measures to reduce civilian casualties, and also to investigate and apologise more quickly when they do kill them. US and NATO commanders say insurgents are still responsible for the majority of civilian deaths. Violence has surged in recent years with Taliban fighters having managed to extend the size and scope of their attacks.