A Pakistani prisoner in India died Thursday after being attacked and hospitalized, dpa cited officials as saying. Sanaullah Ranjay, 52, died of multiple organ failure at a state-run hospital in the northern Chandigarh city. "He was in an extremely critical condition and passed away early this morning," after being in a coma, hospital spokeswoman Manju Wadwalkar said. Ranjay was attacked in the high-security Kot Bhalwal prison in the northern state of Jammu and Kashmir last week, allegedly by a former Indian army soldier. A day earlier, convicted Indian spy Sarabjit Singh died after being attacked in the Pakistani prison where he was held, raising tensions between the neighbouring countries. Pakistan called for an investigation, demanding that those responsible for what it called a revenge killing be brought to justice. "The brutal manner in which Sanaullah was attacked in the jail is most unfortunate and a matter of deep concern for the Government of Pakistan," the Foreign Ministry in Islamabad said in a statement. Indian Home Minister Sushil Kumr Shinde said Ranjay's body will be handed over to Pakistan after autopsy, broadcaster NDTV reported. Ranjay had been serving a life term on militancy-related convictions. India and Pakistan have had troubled relations and fought three wars since their independence from British rule in 1947. The neighbours resumed peace talks in February 2011, but ties have been under strain after India executed Kashmiri militant Afzal Guru over a 2001 attack on the Indian Parliament, and Pakistan-born Ajmal Kasab, the sole surviving gunman from the 2008 Mumbai terrorist attacks.