"We have zeroed in on some (terror) groups -- and have drawn sketches of some people belonging to these outfits. We are in a process of verification and confirmation – whether these sketches match the suspects who were involved in the explosion," Additional Commissioner of Police (Law and Order) Alok Kumar told PTI.
The blast triggered by an Improvised Explosive Device placed in a potted plant had occurred outside the restaurant on Church Street in the city's central business district on Sunday last claiming the life of 38-year-old Bhavani who was on a visit to city from Chennai.
Asked when the sketches would be released, Bengaluru Police Commissioner M N Reddi replied, "Not today."
Earlier, Kumar said police were interacting with various agencies and other state police officials.
"We are interacting with various agencies which have come here, and at the same time we are in contact with other state police forces also. We are trying to have a conclusive link," he said.
Asked if any specific request was being made by police to National Investigation Agency or other agencies, Kumar who is also heading the Special Investigation Team (SIT) to probe the blast said, "No we have not made any specific request. We had meeting yesterday with them (NIA)."
"If there is anything they can share with us or that is required, on the need basis that will be done,”" he added.
On reports that a person has been held in Bihar, Kumar said "we are not aware of that thing and we have not been informed about that arrest."
Meanwhile, drone aerial cameras were being used by police for the first time to monitor New Year celebrations in the central business district where the blast took place.
The remote controlled drones would capture visuals from a height of 50 to 60 metres, which would be monitored live by police which has tightened security on M G Road, Brigade Road, Lavelle Road and Church Street, which form the nucleus of New Year revelry in the city with people gathering in thousands.
"This year we have taken certain extra measures; we are using Drone Aerial Cameras, this will help us to cover larger area as it captures visuals from the height of 50 to 60 metres. The visuals will be monitored live," DCP Central (Bengaluru) Sandeep Patil said.
Patil said ten watch towers, each of which will have two policemen equipped with night vision binoculars, were in place in the area which has been sensitised with the help of bomb disposal squad and anti-sabotage checks.
Patil said from past three days police was being deployed in larger numbers with constables located at a distance of every 100 metres to check the assigned area.
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