Pakistani fighter jets and helicopter gunships Thursday destroyed a militant facility in the restive northwest, inflicting heavy casualties, security officials said. The air strike targeted a militant stronghold in Piochar, a village in the Swat valley, which has been the site of numerous clashes and bombings since last year. "Helicopter gunships and jets targeted militant strongholds in Piochar inflicting heavy casualties on them, but a count was not available immediately," a security official said. "The successful air strike destroyed the targeted militant facility completely," the official said, requesting anonymity.