PESHAWAR - Six persons were killed when a US drone fired four missiles on a house in North Waziristan Wednesday. According to sources, the drone attack was carried out in Haiderkhel area of Tehsil Mir Ali. The house was completely damaged in the attack while several persons were feared to receive injuries in the attack. Sources said that the area was located some five kms east of Mir Ali. Agencies add: A US drone fired four missiles at a militant compound. At least six militants were killed, a security official said. The identities of the dead militants were not immediately clear.