A special court in Chandigarh found Jagtar Singh Tara guilty for assassination of former Punjab chief minister Beant Singh on Friday. The quantum of sentence will be announced on Saturday.
Tara had earlier three times confessed to the court: "I have no regret for killing Beant Singh."
In his confession, he has also said that Shaheed Udham Singh, who assassinated Lieutenant Governor of Punjab Michael O'Dwyer in 1919, was his inspiration to kill the Congress leader.
Beant Singh was assassinated in a bomb blast at the secretariat complex in Chandigarh on August 31, 1995 by Babbar Khalsa International terrorists.
The blast had claimed the lives of 17 others including three commandos. Thirteen people were named as accused in the case, out of whom nine were arrested, three were at large and the suicide bomber, Dilawar Singh, died during the explosion.
Tara, who along with two other terrorists, had fled from the Burail Jail by digging a 110-feet tunnel from his barrack in January 2004, was apprehended in Thailand.