( BBC ) - Pakistani warplanes bombarded suspected pro-Taleban militant positions on Tuesday, as fierce fighting raged near the Afghan border for a fourth day.
The army says 45 troops and 150 rebels have died in battles around the town of Mir Ali. Tuesday's air strikes left 50 rebels dead, unconfirmed reports say.
Locals are fleeing the area in large numbers. They say many civilians died.
It is the heaviest fighting for many months in North Waziristan, which the US says is an al-Qaeda safe haven.
Pakistan's President Musharraf - a vital ally in the US-led "war on terror" - is under pressure to do more to stop militants crossing into Afghanistan, where violence this year has soared.
The BBC's Barbara Plett in Islamabad says that Mir Ali is known as a base for foreign militants with links to the Taleban and al-Qaeda.
The violence has been escalating since mid-July when a ceasefire between the army and the militants broke down.
Access for journalists to the tribal areas is restricted and it is impossible to independently verify the casualty figures.