"He is on ventilator and in deep coma. He continues to be critically sick," said an update on Sanaullah's condition issued by the PGIMER on Saturday night.
"Sanaullah remains on ventilator," it said adding his blood pressure had been going down and his neurological status remained the same.
52-year-old Sanaullah, who was brought to the PGIMER from Jammu on Friday evening, is being looked after by a team of doctors, including neurosurgeons, at the intensive care unit.
Earlier, a medical bulletin said the prisoner's urine appeared to be adequate and "further treatment will depend on his stabilisation and neurological status".
A team of Pakistani High Commission officials visited Sanaullah, a resident of Saialkot in Pakistan, at the PGIMER after India granted consular access to them on Friday night.
The officials again visited the hospital and were in touch with the doctors for regular update on the prisoner's condition.
Sanuallah is serving a life term after being convicted under TADA provisions following his arrest in 1999.
Two prison officials, including Jail Superintendent Rajni Sehgal, had been suspended by the Jammu and Kashmir government in connection with the assault.
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