Pakistani civilians, fleeing from a military operation in North Waziristan tribal agency, arrive with their livestock in Bannu district on June 20, 2014. Pakistani helicopter gunships pounded militant targets in the country’s northwest June 20 killing up to 20 rebels, as the number of civilians fleeing an expected ground offensive passed 150,000. AFP PHOTO/A MAJEED

BANNU (AFP) – Pakistani helicopter gunships pounded militant targets in the country’s northwest Friday, killing up to 20 rebels, as the number of civilians fleeing an expected ground offensive passed 200,000.

Nearly 150,000 people have left North Waziristan tribal area on the Afghan border this week after the military launched a long-awaited assault against Taliban hideouts.

The authorities eased a shoot-on-sight curfew on Wednesday to give civilians a chance to leave before troops begin a full-blooded ground operation.

A senior security official told AFP that helicopter gunships targeted militant hideouts in an early morning raid in Kutabkhel area of Miranshah, the main town of North Waziristan, killing up to 20 militants.

A local intelligence official also confirmed the attack and casualties.

Nearly 250 insurgents have been killed since the start of the operation on Sunday, according to security officials, though it is not possible to confirm the number or identity of those killed.

The military offensive began after a bloody and dramatic attack on Karachi airport last week brought an end to months of largely fruitless government efforts to negotiate a peace deal with the Tehreek-e-Taliban Pakistan (TTP).

Pakistan’s allies, particular the United States, have long called for an operation in the mountainous tribal territory to flush out groups like the Haqqani network, which use the area to target NATO troops in neighbouring Afghanistan.

The area, one of seven semi-autonomous tribal regions on the Afghan border, has been an important base for the TTP, which has killed thousands in bombings and gun attacks during its seven-year insurgency.

The fighting has triggered a huge exodus of civilians from North Waziristan, both into the Pakistani cities of Bannu, Peshawar and Kohat and across the border into Afghanistan.

“Some 157,000 people have arrived in Bannu from different areas of North Waziristan,” Arshad Khan, director general of the FATA (Federally Administered Tribal Areas) Disaster Management Authority, told AFP on Friday.

Registration points and camps have been set up to deal with the influx of people in Bannu, but many prefer to travel on to stay with relatives in other areas.

In Afghanistan, Khost administration spokesman Mubarez Mohammad Zadran told AFP that 1,400 refugee families had registered and estimated that as many as 10,000 families — or 70,000 to 80,000 people — could be scattered across the border province.

The provincial government along with relief agencies and the UN High Commissioner for Refugees (UNHCR) have set up a camp.

– Polio vaccinations –

There are fears the exodus from North Waziristan could lead to the spread of polio infections, as the area is the worst affected in Pakistan by the crippling disease.

On the Afghan side, officials say they have already vaccinated more than 5,500 children against polio, which remains endemic on both sides of the border.

In Pakistan, people fleeing North Waziristan have been given polio drops at a checkpost to enter neighbouring Khyber-Pakhtunkhwa province.

Thousands of people including women and children were seen travelling to Bannu by foot on Friday. Women were sitting by the roadside as vehicles and passenger vans kept moving at a snail’s pace in long queues — the 60 kilometre (40 mile) journey from Miranshah to Bannu taking 16 hours by car, an AFP reporter said.

In Miranshah and Mir Ali, the two main towns of North Waziristan, more than 80 percent of the population have either left or were planning to leave in next 12 hours.

But despite security officials warning that a major ground offensive is imminent, in other areas many people have chosen to remain.

A government official in Miranshah on Friday estimated that up to 40 percent of the whole population of the region could stay behind.

In Razmak, one of the three sub-divisions of North Waziristan, almost half of the population has decided to stay as they believe they will be safe as there was no militant activity in their area.

A senior government official in Razmak confirmed to AFP that a tribal jirga or council met government officials on Thursday and asked to be allowed to stay.

“They told us that not a single drone strike has yet taken place in their areas because of no militant activity in there,” the official said.

So far there appears to have been little resistance from the TTP to the military operation, though this may change once the ground fighting begins.

In Torghar district, around 130 kilometres (80 miles) northwest of Peshawar, a roadside bomb targeting a police van killed one policeman and wounded two others.