Balwant Singh Rajoana, a convict on death row for assassination of former Punjab chief minister Beant Singh, was on Saturday admitted to Government Medical College and Rajindra Hospital after he complained of acute chest pain.
Rajoana has been lodged in the local central jail for the past many years.
Later, doctors referred him to the Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh.
According to information, Rajoana was brought to the local hospital from the jail under a heavy security cover and was immediately admitted to the intensive care unit.
Sources in the jail said the pain started instantly while Rajoana was doing routine physical exercise in his cell.
"The jail doctors sent him to the hospital. The signs of sweat and restlessness could be seen," sources said.
Deputy medical superintendent Dr Harshinder Kaur said with Rajoana constantly complaining of pain on the left side of his chest, the doctors conducted a series of tests. "The results of the test were normal and nothing serious came to the fore," she said.
However, the medical board referred him to the PGI, she added.
One of doctors said Rajoana had earlier also complained of the same thing. "Even after being admitted to the ICU, he continuously complained of chest pain and was given a painkiller injection. He also complained of pain in the spine, where he had undergone a surgery years ago," the doctor said.
Karamjit Singh Sandhu, deputy superintendent of the jail, confirmed that Rajoana was shifted to the PGI.
A former Punjab Police constable, Rajoana was a member of the Babbar Khalsa and one of the main accused in the assassination of Beant Singh in 1995, in which 16 people were killed in the blast outside the Punjab secretariat in Chandigarh.
He was arrested in December 1995 and was given the death sentence in 2006.
Thought he didn't file a mercy petition, in 2012, the Shiromani Gurdwara Parbandhak Committee filed a petition with the President, demanding cancellation of the death sentence.