The information will be shared with Sri Lankan authorities by the National Investigation Agency under the Mutual Legal Assistance Treaty signed between the two countries in 2010, official sources said.
NIA had last month taken over the case which was earlier registered by Tamil Nadu Police in which a Sri Lanka national, Sakir Hussain, was arrested following a tip-off from the Intelligence Bureau.
Hussain was accused of having entered India with a mission to carry out reconnaissance of the US Consulate in Chennai and the Israeli Consulate in Bangalore.
The information under MLAT, which has been cleared for sending to Colombo through diplomatic channels, names Amir Zubair Siddiqui, Consular (Visa) in the Pakistani Mission in Sri Lanka as the main conspirator who was involved in a conspiracy with some Lankan nationals for carrying out terror attacks on the two consulates, the sources said.
Repeated attempts to obtain comments from the Pakistani High Commission's Visa and Information sections failed as there was no reply.
However, earlier, its Press Attache Muhammad Daud Ehtisham was quoted as saying that Pakistan and its state institutions are responsible entities and do not indulge in such activities.
Siddiqui is not a new name for IB as his name had cropped up earlier in 2012-13 when security agencies picked up one Tameem Ansari, a frequent flier between Trichy and Colombo. Ansari was arrested after six months of surveillance in 2012.
A small trader who sent, among other things, potatoes and onions to Sri Lanka, Ansari was in touch with Haji, a Tamil-speaking Muslim from Colombo. However, after his business failed, one Haji allegedly introduced him to Siddiqi in the Pakistan mission in Colombo, and his second in command, Shaji.
After reportedly brainwashing him, Siddiqi roped him in to take videos of the Nagapattinam port, the ships that berthed there, the topography and other dimensions as well as Mallipattinam, traditionally a landing point.
His name again figured after IB, on a tip-off from its Malaysian counterparts, foiled an attempt by ISI to carry out terror attacks on the two foreign consulates in India.
Sakir Hussain told interrogators that he had been hired by Siddiqui in Colombo as per the alleged ISI plans to conduct reconnaissance of the US Consulate in Chennai and Israeli Consulate in Bengaluru.
The case was eventually transferred to NIA as overseas investigation was required into it. Hussain told interrogators that the Pakistani spy agency was planning to send two men from the Maldives to Chennai and that he had to arrange for their travel documents and hideouts.
During interrogation, Hussain reportedly took the name of Siddiqui as his alleged handler and also said he had been chosen as he was engaged in human trafficking, making of forged passports and smuggling of fake Indian currency.
Sleuths had recovered pictures of the US and Israeli consulates showing various gates and roads leading to the two premises, the sources said, and claimed that these pictures had been mailed to his alleged handlers in Pakistan and its High Commission in Colombo.
Cyber signatures showed that the pictures were downloaded in a computer within the premises of Pakistan High Commission at Colombo and the same had been shared with Sri Lankan authorities, the sources claimed.
Now, under MLAT, Sri Lankan authorities have been asked to share their probe details in the case.
Under the treaty, both countries will provide assistance in locating and identifying persons and objects; taking evidence and obtaining statements; authorising the presence of persons from the Requesting State at the execution of requests; facilitating the appearance of witnesses or the assistance of persons in investigations, among others.
Sri Lankan authorities were carrying out a probe at their end to fill in the gaps in the investigation being undertaken by India besides corroborating the versions of Hussain and another accomplice of his, Mohammed Hussain Mohammed Sulaiman, who has been arrested by Malaysian authorities who stumbled upon the plot when its Special Unit was probing money laundering and human trafficking cases.
A Sri Lankan citizen, 47-year-old Sulaiman is wanted in India for allegedly hatching a criminal conspiracy, acts done by several persons in furtherance of a common intention, possession of forged or counterfeit currency notes or bank notes, terrorist acts, and raising funds for terrorist acts. He is considered crucial for the investigation.
Sulaiman has told Malaysian authorities that he had received instructions to assist two men in the planned attacks on the consulates.
The sources said that the apparent strategy being followed by Inter-Services Intelligence was to rope in Muslims from Sri Lanka for executing their plans to give credibility to the deniability factor that it was not involved in any way.
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