The government says all those who were killed in the January 21 operation were militants, but local residents in the volatile region bordering Afghanistan said the death toll included many civilians.

The Pakistani army was not available for comment on the possibility of further operations.

Prime Minister Nawaz Sharif has been under intense pressure from hawks within his administration to take aggressive military action against the Taliban after his efforts to engage them in talks floundered in recent months.

The air strikes last week came a day after a Taliban suicide bomber killed 13 people in a crowded market near Islamabad and two days after the Pakistani wing of the Islamist militant group killed 20 troops in the northwest town of Bannu.

Fearing another offensive by armed forces, a wave of refugees left the region to take shelter in schools, private homes and veterinary clinics in the normally more peaceful areas of Bannu and Dera Ismail Khan on the edge of the tribal belt.

A senior official in Bannu said 23,000 refugees had fled to the town.

"Innocent women and children were hit in the air offensive in North Waziristan," said Janaat Bibi, 90, a refugee in Bannu, who added that she was suffering from high fever.

"We walked on foot for several kilometres at night until the bombing died down. Then we got a lift on a tractor and arrived in Bannu,” she said.

People in North Waziristan, a land of rocky mountains and steep valleys that is home to several al Qaeda-linked groups, live in constant fear of being targeted by both the Taliban and government troops.

"They are moving their families in anticipation of an army operation," said a government relief official, who spoke on condition of anonymity.

"There is no operation going on and we as a government body have not been informed about it either, but the people seem to be afraid.

They want to flee before there is a state of emergency,” he said.

Many refugees in Bannu said the government had made no arrangements to provide them with shelter.

A charity wing of Jamaat-e-Islami, a radical Islamist organisation, was seen distributing rations and blankets to the refugees - a frequent sight in Pakistan where Islamist groups often step in to offer relief during crises.

"We were forced to leave our house behind by the heavy pounding of the jets. On our way to Bannu we were harassed at several check posts by security officials," said 26-year-old Najeebullah, who fled with 25 members of his family.

"We will not return to our homes unless were satisfied that there will be no more bombings,” added Najeebullah.

(Agencies)

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