The blast went off on the train heading to Pakistan's Lahore from India's New Delhi on Feb. 18, 2007, leaving 68 people, mostly Pakistani nationals, dead. "Today the court acquitted Swami Aseemanand, Lokesh Sharma, Kamal Chauhan and Rajinder Chaudhary in the Samjhauta train blast case.

The court said prosecution has failed to prove involvement of the accused in the case," a local government official said on  Wednesday. Aseemanand, the former right-wing Rashtriya Swayamsevak Sangh (RSS) activist who was charged in three terror attacks a decade ago, was accused of providing logistic support to the persons who carried out the blast. 

RSS is considered as an ideological fountainhead of Bhartiya Janta Party. While Aseemanand was out on bail, the three others were in judicial custody.

India's anti-terror agency -- the National Investigation Agency (NIA) which took over the probe in the case in 2010, said that the accused were upset with the terror attacks on several Hindu temples and conspired to trigger the blast in the Pakistan-bound train for vengeance.

However, the special court ruled that the investigative agency failed to prove its charges.The Samjhauta Express is jointly run by the railways of India and Pakistan. The bi-weekly train service runs between Delhi and Attari in India and Lahore in Pakistan.