peshawar school attack
Pakistani soldiers transport rescued school children from the schoolA Majeed/AFP

A teenage girl caught in the Peshawar attack by Taliban militants managed to survive a gunman's assault by playing dead, according to local reports.

Shireen Khalid Wadud told the BBC that her friend's daughter, a 13-year-old student at the school attacked by the Taliban, was in her class when a gunman burst into the room.

"She pretended to be dead," Wadud said. "When the gunmen left the class, she ran and managed to escape.

"She was the only person who could escape from the class...She is wounded in her leg, but fortunately it is not serious. She is in hospital. She is very panicked and she is frightened."

Wudud's account could not be independently verified but a number of shocking stories are emerging from the brutal attack by the Taliban, including unconfirmed reports that "headless" bodies have been arriving at local hospitals.

At least six militants entered school in north-west Pakistan, wearing security uniforms, before massacring at least 130 people and injuring 122, with a number of explosions reported.

The attack by militant group Tehrik-i-Taliban Pakistan (Pakistani Taliban) took place in response to Pakistani military operations against the group but a Taliban expert said there was also a possibility that the school was targeted because education activist Malala recently won the Nobel Peace Prize.

Malala joined the chorus of condemnation against the "atrocious and cowardly" attack on the Pakistan school.

"I am heartbroken by this senseless and cold-blooded act of terror in Peshawar that is unfolding before us. Innocent children in their school have no place in horror such as this.

"I condemn these atrocious and cowardly acts and stand united with the government and armed forces of Pakistan whose efforts so far to address this horrific event are commendable.

"I, along with millions of others around the world, mourn these children, my brothers and sisters - but we will never be defeated."

A three-day period of nationwide mourning has been announced by Pakistani Prime Minister Nawaz Sharif while chief spokesman for the Pakistani army Asim Bajwa confirmed that six terrorists have been killed in their operation against the group.