Safdar Nagori, the general secretary of the proscribed outfit Student's Islamic Movement of India, was in Mumbai on July 11, 2006, when a series of explosions in suburban trains claimed 187 lives and injured thousands.
"He was in the city between July 7 and 12. But it is not clear as to where he was and what he was doing," said a senior officer from the Anti-Terrorism Squad.
Nagori is said to be acquainted with serial train blasts case accused and SIMI's Maharashtra unit general secretary Ehtesham Siddiqui. He is also wanted in a case filed in Mumbai under the Unlawful Activities Prevention Act, in which Siddiqui was first arrested.
However, investigators have not been able to establish any link between Nagori and the serial blasts. The ATS will demand that Nagori's custody be handed over to it for further investigations. He was arrested by the Madhya Pradesh police last month.
During interrogation by the Maharashtra ATS officers in Madhya Pradesh, Nagori has said he had traveled to Mumbai after the conclusion of a three-day meeting of the SIMI in Ujjain on July 6, 2006.
"Nagori was in the city till July 12, after which he is said to have embarked on a tour to some other destination. Such men do not break easily (in interrogation) and we will have to ascertain his movements in the city through his mobile phone records," the officer said.
Top SIMI leaders had met in the jungles near Ujjain in Madhya Pradesh to discuss organisational matters between July 3 and 6, 2006.
The ATS is also 'surprised' by a letter allegedly written by Siddiqui, while in custody in connection with the serial blasts case, to Nagori. The letter was recovered from Nagori's hideout in Madhya Pradesh, the officer said.
"In the letter, Siddiqui writes that he has not divulged any details regarding the July 11 serial blasts conspiracy to the interrogators in spite of every effort made by them," the officer said.
It is possible that the letter was not sent through the jail authorities fearing a scrutiny. Siddiqui may have sent the letter through an advocate or some relative who would have come to meet him in jail, he said.
"We will confront both of them (Siddiqui and Nagori) and ask them about the letter. After the discovery of the letter, the Madhya Pradesh police may also be interested in taking Siddiqui's custody. Otherwise, we will apply for Nagori's custody," said the officer.
Nagori and other SIMI activists are in the MP police's custody till April 18 and police forces from over five states have shown interest in taking their custody.
Nagori was arrested along with 12 other activists of the banned SIMI while they had come for a meeting near Indore on March 26 this year. This has led to the arrest of over 50 alleged members of the outfit, including two from the outskirts of Mumbai.