Additional District and Sessions Judge R K Sondhi handed down the sentence to Bheora, who headed the terrorist outfit's operations in India and was arrested in 1997, after he was held guilty for criminal conspiracy and for his involvement in killing of Singh in a car blast on August 31, 1995 at the high-security Punjab civil secretariat complex.
However, counsel for Bheora, Arvind Thakur, told media persons outside the high security Burail jail where the trial was held in a makeshift court that they will challenge the verdict in the higher judiciary.
The CBI had booked nine persons in connection with the killing of the then chief minister outside Punjab and Haryana secretariat on August 31, 1995.
Jagtar Singh Hawara and Balwant Singh were awarded death sentence in 2007. The other accused Gurmeet Singh, Lakhwinder Singh and Shamsher Singh were awarded life imprisonment.
The trial had virtually come to a halt after three of the accused - Hawara, Jagat Singh Tara and Bheora -- escaped from the high-security Burail jail in Chandigarh by digging a 100 ft-long tunnel in January 2004.
But, it resumed in February 2004 following the re-arrest of Hawara and Bheora though the police have been unable to catch Tara.
The special court, which was held at Burail jail here where the accused was lodged, was told by the CBI that Bheora had helped another suspect Jagtar Singh Tara in bringing the car used in the blast inside the secretariat premises in Chandigarh.
Bheora's trial was segregated by an order of the court after his re-arrest from New Delhi in 2006.
Naseeb Singh was awarded a jail term of 10 years along with a fine Rs 10,000 but he was released as he had already been jailed for as many years. Only Navjot Snngh had been acquitted.