This isn't proof?:
KARACHI: In a major breakthrough in the 2007 Samjhauta Express blast case, the Indian authorities on Saturday arrested Rajesh Chaudhary, suspected to have planted bombs in a Pakistan-bound train, Press Trust of India reported.
Rajesh Chaudhary alias Samundar was arrested from Ujjain, Madhya Pradesh. There was a bounty of Rs 500,000 on his head also.
The blast, in 2007 had left nearly 70 dead and 100 injured most of them Pakistanis.
The National Intelligence Agency (NIA) has already charged Aseemanand,
Sunil Joshi (now dead), Lokesh Sharma, Dange alias Parmanand and Kalasangra for hatching a criminal conspiracy which resulted in blasts in the Samjhauta Express near Deewana railway station in Haryanas Panipat district, about 80 km from Delhi.
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I remember that attack initially being blamed on LET. Also here is proof of Purohit's involvement
The ATS suspects Purohit supplied the explosive to a person named Bhagwan who is believed to be a link in the bomb blasts.
Seeking an extension of police custody of Purohit, Special Prosecutor for Maharashtra ATS Ajay Misar told a Nashik court that a witness in the Malegaon blast case told the agency that Purohit had claimed he had 60 kg of RDX in his possession which he had got from J&K.
Misar said: When Purohit was stationed at the Deolali army camp, he had gone to Jammu and Kashmir on official work and is believed to have got 60 kg of RDX and a part of it was given to this link Bhagwan, who used it in the Samjhauta train blast. The ATS is probing his involvement.
Purohit handed over the RDX to Bhagwan who is suspected to be in hiding in the garb of a godman. So Bhagwan is a key link and we hope to learn about his whereabouts and antecedents in the three-day remand given, Misar told The Indian Express.
Purohit supplied RDX for Samjhauta bomb: ATS - Indian Express