Women and children were among 17 civilians killed in southern Afghanistan, an official said on Friday, but it was not clear if they were victims of a foreign air strike or Taleban rockets. The issue of civilian casualties is an emotive one in Afghanistan and feeds the perception of many Afghans that foreign troops do not take enough care to avoid killing ordinary citizens and fuels resentment at the NATO presence in the country. “Around 17 civilians were killed when a house collapsed on them, but we don't know whether the foreign forces' air strikes or rocket attack caused it,” said Dawood Ahmadi, a spokesman for the governor of Helmand province. The chief of the tribal council of Naad Ali district, where the deaths occurred on Thursday, said air strikes killed 18 members of five families sheltering in the house from fighting. “Loy Bagh village where the house was bombed is relatively calm compared with other villages in the district,” said Abdul Ahad Helmandiwal said. “We are still taking out dead or wounded people from the rubble.” The NATO-led International Security Assistance Force (ISAF) said it was investigating an incident involving an air strike in Naad Ali district, but said it was unable to confirm any civilian casualties. A Reuters witness in Lashkar Gah, the nearby provincial capital of Helmand, said he saw six wounded people, including two children and a woman, brought to the hospital. Their families said they brought the wounded from Naad Ali district. But the fatalities could not be independently verified due to clashes between Taliban fighters and ISAF-backed Afghan troops in the district, just west of Lashkar Gah. The Afghan government sent a battalion of troops to Lashkar Gah on Thursday as reinforcements after at least two attempted Taliban attacks on the provincial capital in the past week which were halted by air strikes. In a separate incident, Afghan and foreign troops killed and wounded around 50 Taleban insurgents in the Nerkh district of Maidan Wardak province, on Thursday, provincial governor spokesman, Adam Khan Seerat said.