The probe into the twin blasts in Chennai on Thursday is making slow progress and the main clue that the police have at the moment is regarding two persons who fled the place after the bombs exploded.
One woman passenger was killed and 14 others were injured after two low-intensity blasts rocked the Bangalore-Guwahati Express at the Chennai Central railway station on May 1.
The police after studying almost two and half hours of footage both at the Bangalore and Chennai railway stations have found one man said to be in his early 40s making a hurried escape from the train.
While there is a hunt on for this man, the police are also questioning four suspects in connection with the case. These persons are said to have been on the train at the time of the incident.
The police are also examining the eye witness accounts who have spoken about the two persons boarding the train in Bangalore and were seen to be moving around suspiciously in the two compartments where the bombs went off.
Sources in the intelligence agencies say that the operation could have been planned by a module in Bangalore and the execution was done by two to three persons. Sources also point out that while there was no indication to show that the bombers were trying to target anyone in particular, the intent solely was to scare the people and make an announcement.
Sources in the Bangalore and Chennai police departments say that there are several outfits which are under the scanner.
"We are looking at the possible role played by Abu Bakr Siddiqui who also happens to be the mastermind of the blast outside the BJP office in Bangalore in April 2013. We are looking into all similarities and what we gather is that there is great deal of resemblance between the Chennai blast and also the blasts near the BJP office in Bangalore and the Patna blasts. The nature of the bombs used in all these three blasts is exactly the same. There are improvised explosive devices and ammonium nitrate attached to a timer device,” a senior police official informs.
However, while the bomb composition shows an Indian Mujahideen signature, the police do not want to jump to that conclusion as of yet. Even a group such as the Al-Ummah, which has a better presence in Bangalore and Tamil Nadu, have used similar bombs, they point out.
The Al-Ummah as a group has been targeting political assassinations and they have had a great success rate in the past. Their presence spreads across three states -- Andhra Pradesh, Tamil Nadu and Karnataka.
The blast outside the BJP office in Bangalore led to a detailed investigation and it was found that Abu Bukr Siddiqui, who headed the operation, had managed to build a good network in the three states.
Siddiqui, according to the confessional statements of arrested Al Ummah operatives Bilal Malik, Panna Islamil and Faquruddin, had been sourcing explosives from Udupi in Karnataka, the same place from where the Indian Mujahideen lifted its first ever consignment of ammonium nitrate.
They have managed to source nearly 200 detonators, 6 pipe bombs and 17 kilograms of ammonium nitrate. A lot of this was stocked in Bangalore and some was taken to Tamil Nadu, the arrested trio had told the police.
These operatives also said that they reported to Siddiqui who was the head of the organisation. Siddiqui was not only part of the planning, but was also the person who ensured that the outfit was properly funded.
The Al-Ummah wants to make its presence felt in South India and anyone part of a Hindu outfit, the BJP or remotely connected to the BJP are their targets, the interrogation of the three persons suggested.
Image: CCTV footage points out towards a suspect in the blasts case.
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