Two of the SIMI activists, among the eight killed in an encounter near Bhopal, were wanted by Tamil Nadu police in connection with the 2014 train blast case.
Warrants obtained for bringing them to the city remained pending due to concerns that they might escape in transit.
Sources in CB-CID, which investigated the 1 May 2014 blasts on a Bengaluru-Guwahati train at the Chennai Central station which killed a young software engineer, said the Madhya Pradesh police were apprehensive that the duo might escape if they were sent to Tamil Nadu.
Out of the three accused in the case, Aijajudeen was killed in an encounter by police on 4 April 2015 at Suryapet in Telangana and the remaining two Zakir Hussain, and Mehboob died in the encounter on Monday.
Their death virtually brings the curtains down on the case.
Both Zakir Hussain alias Sadiq and Mehboob alias Guddu had escaped from Khandwa jail in Madya Pradesh in 2013.
A prisoners’ transit warrant was obtained to bring Zakir Hussain and Mehboob to Chennai in connection with the Chennai blasts case. However, MP authorities were concerned. They thought that the duo may try to escape if sent out.Senior Police Official
He said by July this year, the PT warrant was obtained for the duo, however, it remained pending.
Another official said, "all legal procedures will be followed in the case" with the death of the accused persons, but did not elaborate.
He said the links of the accused to several crimes in more than one state involved probe by multiple state and central agencies.
The SIMI activists, called "Khandwa module" in police parlance, were behind a number of serious crimes.
After their escape in 2013, they were involved in a number of crimes including the Rs 46 lakh heist at SBI's Choppadandi branch at Karimnagar in Telangana in February 2014, police said.
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