NEW DELHI (AP) -- Indians expressed outrage over the death Thursday of a convicted Indian spy who was bludgeoned with a brick by two fellow inmates at a Pakistani prison. Government officials said the incident had badly damaged relations between the two nuclear-armed neighbors.
Sarabjit Singh had been comatose and on a ventilator for days after the prison attack last Friday. He died at Jinnah Hospital in the eastern city of Lahore, triggering questions as to why he was left vulnerable inside the prison.
Zulifqar Hameed, a senior Pakistani police investigator, said police were questioning the two men who attacked Singh and took initial steps to charge them with murder.
India's foreign minister, Salman Khurshid, said ties between the nations "have been hurt by this terrible tragedy."
"For the present, I can only say that it is a terrible psychological and emotional setback to all of us and I believe to what we have been trying to do in terms of creating greater cohesion between people of India and people of Pakistan," Khurshid told reporters.
Singh was arrested in 1990 after bombings killed 14 people in Lahore and Faisalabad, Pakistan. He was convicted of spying and carrying out the blasts and sentenced to death.
His family, which received a condolence call Thursday from top ruling Congress party official Rahul Gandhi, maintained Singh was innocent and had entered Pakistan inadvertently from his hometown of Bhikiwind in the border state of Punjab.
Indian Prime Minister Manmohan Singh said it was "particularly regrettable" that Pakistan had brushed off pleas to make a humanitarian gesture and allow Sarabjit Singh to return to India after he had served 20 years in prison.
The opposition accused the government of not doing enough to fight for Singh's release. Manish Tewari, India's information minister, said the government had been pressing Pakistan to release the prisoner since 2005.
Singh's sister Dalbir Kaur, who visited him in the Lahore hospital early this week, said she had asked the Indian government to seek tighter security for Singh after New Delhi hanged Mohammed Afzal Guru, a Kashmiri man, in February. Singh had feared being attacked by other inmates in retaliation, she said.
Guru was convicted in a 2001 attack on India's Parliament that left 14 people dead. Several rights groups across India and political groups in Indian-controlled Kashmir have said that Guru did not get a fair trial. Pakistan's lower house of Parliament passed a resolution condemning the hanging.
India and Pakistan have fought three major wars -- including two over Kashmir -- since they achieved independence from Britain in 1947. Relations have experienced ups and downs in recent years.
Rajnath Singh, president of the main opposition Hindu nationalist Bharatiya Janata Party, demanded India scale down diplomatic ties with Pakistan.
"The Indian high commissioner in Pakistan should be called back for the time being until Pakistan gives credible assurances that it will not allow its territory to be used to promote terrorism against India and that all Indian prisoners are safe in Pakistani jails," he told reporters.
Foreign ministry spokesman Syed Akbaruddin said India is demanding a thorough investigation of the attack.
"This was simply the killing of an Indian citizen while in the custody of Pakistani authorities," he said in a statement. The attack "highlights the need for a concerted action by Pakistan to safeguard Indian prisoners in Pakistan."
Associated Press writers Sebastian Abbot, Zarar Khan and Munir Ahmed in Islamabad, Pakistan, contributed to this report.
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