Bengaluru blast
Bengaluru Police at the bomb blast site on Church Street.IANS

While speculations about an ISIS hand in the Bengaluru blast are rife, with even Chief Minister Siddaramaiah stating that it could be in retaliation to the arrest of Shami Witness' Mehdi Masroos Biswas, counter-terror experts have said the Middle East terror group may not be connected with the incident at all.

"The arrest of the ISIS supporter and the blasts on Sunday within a few weeks is just a coincidence," Sameer Patil, associate national security, ethnic conflict and terrorism fellow at Gateway House, a Mumbai-based think-tank told IBT India. Patil is a former official of the National Security Council.

"It is more likely that a module of the Students' Islamic Movement of India – Indian Mujahedeen – is behind the blast," he said.

Patil said that after several key IM operatives were arrested this year, the terror group has been reduced to carrying out low intensity IED blasts. "Even the recent blast in Pune during the Ganesha festival was linked to SIMI-IM. It is an attempt to showcase their relevance and to test the resolve of the Indian security establishment," Patil said.

Earlier on Monday, Minister of State for Home Affairs Kiren Rijiju had said that the blast was a "terror attack" possibly carried out by Students Islamic Movement of India (SIMI), and the Karnataka police are now probing the role of five SIMI members who escaped from a Madhya Pradesh jail in October.

One Chennai woman was killed in the blast when an IED exploded in front of a restaurant on Bengaluru's Church Street on Sunday night. The blast comes weeks after the arrest of Biswas, who ran one of the most influential pro-ISIS Twitter accounts 'Shami Witness', thus triggering speculations and chatter of an Islamic State-angle.

However, Rajeshwari Krishnamurthy, a research officer in the Centre for Internal and Regional Security at the Delhi-based Institute of Peace and Conflict Studies, thinks the blast has no connection with ISIS.

"The Bengaluru blast does not seem like it has anything to do with retribution by the Islamic State itself or by its supporters. If it were, they would have claimed responsibility for it. Also, India is not the only country to have jailed an ISIS supporter. It has happened in several nations, and there has been no significant retaliation by ISIS in those particular countries per se," she told IBTIndia.

She further said a copy-cat attack by an ISIS support also seemed like a 'faint' possibility.

"This attack appears to have been orchestrated by the SIMI, as it has carried out similar attacks before," Krishnamurthy said, who also ruled out the involvement of al-Qaeda, whose chief had recently warned of terror strikes in India.

"While it will be a long-shot to think that the al-Qaeda, which had threatened of attacks in India, could be involved, had they been directly involved, the attack would have been on a much larger scale."