A top Pakistani prison official says an Indian spy on death row was critically injured when he was attacked with a brick inside a prison in the eastern city of Lahore.

Farooq Nazir said Friday that Sarabjit Singh sustained a serious head injury when he was attacked by two other prisoners on Friday at Kot Lakhpat jail. Nazir said Singh was moved to hospital and was out of danger.

Singh was arrested in 1990 for his role in series of bombings in Lahore and Faisalabad that killed 14 people.

He was convicted of spying and carrying out the bomb blasts and sentenced to death in 1991. The sentence was later upheld by Pakistani superior courts.

Former military ruler Pervez Musharraf rejected his mercy petition in 2008.