At least three people were killed and half a dozen injured on Friday as a US drone attacked a house in Pakistan's tribal area along the Afghan border, according to DPA. A security official said a pilotless US drone fired missiles at a house in Mohmmad Khel village in North Waziristan. More casualties were feared as some people were believed to be buried under the rubble, said the official, who spoke on condition of anonymity. However, a spokesman from the Pakistan Army denied the report saying the US planes only hit targets on Afghan side of the border. "The International Security Assistance Force had informed us beforehand about their operation along the border in Afghanistan," Major General Athar Abbas said. The US attack came three days after two missiles fired from a US drone killed six people in North Waziristan, which is regarded as a haven for Taliban militants and members of the al-Qaeda terrorism network.