Fierce fighting has broken out as Pakistan's army launched an air and ground offensive against Taliban militants in the South Waziristan area.
Officials said 30,000 troops, backed by artillery, had moved into the region where Pakistan Taliban leader Hakimullah Mehsud is based.
Militants were reported to be offering stiff resistance as troops advanced from the north, east, and west.
A curfew was imposed in the region before the offensive began.
There have been several co-ordinated Taliban attacks in recent days, killing more than 150 people in cities across Pakistan.