The Pakistani army has launched what it calls a "comprehensive operation" to wipe out Islamist militants in the North Waziristan region.
It follows last week's attack on an airport in the city of Karachi, for which the Pakistan Taliban claimed responsibility.
An air strike on militant bases last night was claimed to have killed about 100 militants, many of whom are thought to have been foreign fighters.
"Our valiant armed forces have been tasked to eliminate these terrorists regardless of hue and colour, along with their sanctuaries," the army said in a statement.
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