Police conducted raids and detained a "number of persons" in connection with the serial blasts that rocked this city killing at least 38 people and injuring around 90 others.
Joint Commissioner of Police of Crime Branch Ashish Bhatia told PTI on Sunday that no arrests have been made so far.
Bhatia also said that there was no evidence as yet to suggest the involvement of a suicide bomber in the blast that occurred at the civil hospital on Saturday.
"Our teams conducted search operations at various places last night and detained number of persons. I cannot provide the exact figure as many teams were involved in the operations and we are yet to consolidate the figures," he said.
"There are some rumours going on. But I do not suspect an suicide bomber was used at city civil hospital. Upper half of a person was found at the site after the blast. He has not been identified yet. May be this might have fuelled the rumour," Bhatia said.
"But I do not think any suicide bomber was involved," he added.
When asked how the blast at the civil hospital took place, Bhatia said that the bomb was kept in a car near the Trauma Centre of the hospital.
"The car in which the bomb was kept was blown to pieces. Some small gas cylinders were found at the site. This could have increased the intensity of the blast," Bhatia said.