Pakistan's government has reimposed its curfew in the Swat valley after lifting it earlier to allow thousands of residents trapped by fighting to leave.
Pakistan hopes to stop a growing Taliban insurgency with its offensive in the former tourist valley after US criticism that the government was failing to act against militants.
Hundreds of thousands of people have left Swat in the past week and in all about 500,000 are expected to get out.
They join 555,000 people displaced earlier from Swat and other areas because of fighting since August.
The army went on a full-scale offensive on Thursday after the government ordered troops to flush out militants from the Taliban stronghold.
The offensive was launched while President Asif Ali Zardari was in Washington assuring the US that his government was committed to fighting militancy.
Fighting had intensified two days before the offensive was launched, triggering a civilian exodus as a February peace pact collapsed, but concern has been growing for those trapped and unable to move because of the curfew.
The exodus resumed with the lifting of the curfew for seven hours today although residents said transport was scarce because the military was not letting vehicles into the valley.
