The explosion that took place in front of Nagaland House and Hindusthan Lever building was so severe that a railing on the pavement was uprooted and glass panes of the adjacent building shattered under its impact.
Police here said that the injured were pedestrians. The condition of one of them in hospital was treated to be serious.
A large contingent of police have rushed to the spot and cordoned the area, while sniffer dogs have been brought in to detect the existence of any explosive.
However, City Police Commissioner Gautam Mohan Chakraborty, who visited the area, said the explosion was possibly caused by a short circuit in the underground cable lines.
''In all probability, it was an explosion in the underground cable lines, which may have been triggered by a short circuit. But, there is nothing to worry about,'' he told UNI.
DC DD1 Javed Shamim also said, ''So far no explosives have been detected by the sniffer dogs, though forensic experts were being broght in for a detailed investigation.'' The incident before the Republic Day, however, kept city police on their toes, while people ran in panick and shopkeepers kept shutters down for sometime today.