London: Nobel Peace prize winner Malala Yousafzai on Wednesday said she is "heartbroken" by "the senseless and cold blooded" killing of scores of children by Taliban militants at an army-run school in Pakistan.

"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," Malala said in a statement.

As many as 141 people, nearly all of them school children, were massacred when heavily armed Taliban suicide bombers stormed a school in Peshawar, firing indiscriminately, leaving another 130 injured.

"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," she said.

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

Seventeen-year-old Malala, who now lives and studies in Birmingham, became a global icon after she was shot in the head by the Taliban in October 2012 for standing up for the right of education to girls in Pakistan.