Four of the 13 people accused of involvement in the July 11 blasts in commuter trains in Mumbai had allegedly gone to Pakistan via Iran to learn how to make bombs at a training camp run by Lashkar-e-Tayiba leader Azeem Cheema.
This was revealed in the chargesheet filed by the Anti-Terrorism Squad in a special court in Mumbai on Thursday.
The ATS said it had ample circumstantial evidence to indicate that the men had travelled to Pakistan.
Tanveer Ahmed Mohammed Ansari, Muzammil Ataur Rehman Shaikh, Suhail Mohammed Shaikh and Zameer Ahmed Latifur Rehman Shaikh had allegedly travelled to Pakistan via Iran on a 'jiyarat' visa.
The chargesheet said members of the Shia sect of Islam normally visit Iran on such visas to make a pilgrimage to the tomb of religious leader Imam Raza at Mashad.
In this case, the visas of the four men were not stamped as required at Mashad.
This indicated that though they travelled from India to Iran, they did not visit Mashad, but instead crossed over to Pakistan from Iran, the chargesheet alleged.
"The non-appearance of stamp/seal on their 'jiyarat' page are conclusive proof of the same," said the chargesheet filed four months after the blasts that killed nearly 200 people. It had also come to light that the men travelled individually to avoid being caught together, it alleged.
The chargesheet said accused Mohammed Faisal went to Pakistan for training in handling explosives on October 1, 2001, and returned on November 29 the same year through the Wagah land border post.
He made a second visit to Pakistan in November 2003, when he left Mumbai for Jeddah and illegally entered Pakistan via Kisham island in Iran, where he allegedly destroyed his Indian passport, the chargesheet said.
During his return, his mentors in Pakistan gave him a fake Pakistani passport in the name of Mohammed Akram, using which he returned to Jeddah.
While in Saudi Arabia, Faisal was arrested for not possessing a travel document and deported to Delhi on an emergency certificate.
During both these visits, he received training in the use of arms and explosives at a training camp of LeT leader Azeem Cheema who asked Faisal to recruit Muslim youths for arms training in Pakistan and to survey targets for terrorist attacks.