PESHAWAR: A Pakistani child activist shot in the head by the Taliban is still in a critical condition and is being airlifted to the country's top military hospital for specialist treatment, officials said Thursday.

The shooting of 14-year-old Malala Yousafzai on a school bus in the Swat valley has been denounced worldwide and by the Pakistani authorities, who have offered a reward of more than $100,000 for the capture of her attackers.

Two of her school friends were also injured in the attack, carried out as retribution for Malala's campaign for the right to an education during a two-year Taliban insurgency in Swat that the army claimed to have crushed in 2009.

But as she spent a second day in intensive care questions are mounting about how the attack could have happened in the first place and how the perpetrators simply walked away in an area with a police and army presence.

“Now she needs post surgery care. The doctors recommended that AFIC (Armed Forces Institute of Cardiology) has better facilities for post-surgery care,” military spokesman Major General Asim Saleem Bajwa told AFP.

Another official confirmed that a helicopter transporting her from the hospital in Peshawar to Rawalpindi, the twin city of the capital Islamabad and the headquarters of the Pakistan army, was making the 25-minute journey with Malala on board.

Bajwa said Malala was still unconscious and that the next 24 hours would be crucial to her progress. On Wednesday, she underwent an operation to remove the bullet from between her shoulders.

One of her doctors, Mumtaz Khan, told AFP that Malala had improved since the operation but that she was still seriously ill.

“She has been put on a ventilator for two days. The bullet has affected some part of the brain, but there is a 70 per cent chance that she will survive,” he said.

Mehmoodul Hasan, one of Malala's relatives, said the family had been told that doctors were sending her medical reports abroad for advice.

“They are checking if better facilities are available in the UK or Dubai or any other country, then they will decide about sending her abroad, otherwise they will treat her here,” said Hasan.

US President Barack Obama, US Secretary of State Hillary Clinton, UN chief Ban Ki-moon and Pakistani leaders have expressed horror at the attack on a girl who won admiration for daring to speak out during the Taliban insurgency, which the army said it had crushed in 2009.

Obama believed the shooting was “reprehensible and disgusting and tragic,” said White House spokesman Jay Carney.

Malala won international prominence after highlighting Taliban atrocities in Swat with a blog for the BBC three years ago, when the Islamist militants burned girls’ schools and terrorised the valley before the army intervened.

She was just 11 then, and her struggle resonated with tens of thousands of girls denied an education by Islamist militants across northwest Pakistan, where the government has been fighting local Taliban since 2007.

The Pakistani provincial government announced a 10 million rupee ($104,000) reward for information leading to the arrest of Malala's attackers and Interior Minister Rehman Malik has promised to catch the gunmen.

Officers in Swat say dozens of people were rounded up after the attack but no one has been charged.

Local residents say four businessmen and outspoken anti-militancy advocates have been shot in Swat in recent months, raising fears about the scenic valley which Pakistan has been trying to restore as a tourist destination.

Mingora police station chief Ahmad Shah told AFP that nearly 200 people had been detained over Malala's shooting, including the bus driver and a school watchman, but that most had been released.

Commentators have questioned whether anything will really change in Pakistan after the shooting, despite a call from the army chief General Ashfaq Pervez Kayani to further unite against militants and their “barbaric mindset.”

Many in the country blame the United States and the war in neighbouring Afghanistan for the violence. The military has been accused of playing a double game in supporting or at least accommodating Islamist militant groups.

The Taliban, who have killed thousands of people across Pakistan in the last five years and destroyed hundreds of girls' schools, have issued a statement saying that any female who opposes them should be killed.