The volume of these footages, which are playing a crucial role in helping investigators trace the sequence of events that led to the blasts, is huge and many of the images are not clear.
"There was a need to enhance the images. We are taking help of technical experts of a foreign-based firm for this job," a police official said.
The investigators had also found a photograph of an unidentified person at one of the locations in the CCTV footages and through enhanced image, the face of the person can be easily seen, the official said. Nineteen people were killed and over 130 injured in the three blasts on Wednesday.