Forensic experts have confirmed that the explosive used in Sunday’s Church Street blast was an eight-inch aluminium pipe bomb.

“Investigation is looking into whether the terror attack was the handiwork of [a] fugitive SIMI module,” Chief Minister Siddaramiah said here on Monday.

Investigators said the blast bore similarities with the Chennai Central Station attack in May, and a blast in Pune in July.

Investigators also found a small piece of paper with a Warangal number on it. The number is being verified, and a police team has left for Andhra Pradesh.

Police are looking for clues in images from 11 CCTV cameras in the vicinity of the blast.

Police teams from Maharashtra, Madhya Pradesh and Tamil Nadu have joined the Bangalore police in the investigations, in addition to the National Investigation Agency.

Security agencies suspect the involvement of a SIMI module of five activists who had escaped from Madhya Pradesh’s Khandwa district jail in October 2013.

According to sources, there had been a specific intelligence alert from the Intelligence Bureau in the first week of December alerting the State that two of the five fugitives were last seen in Hosapete of Ballari district in September.

Source: TH