"I appeal to all state governments to install CCTV cameras in all mega cities at the earliest...so that if any incident takes place, a proper investigation could be carried out," he told reporters after meeting officials of investigating agencies at his office.
A woman died and three others were injured in the blast near a restaurant in Bengaluru Sunday.
"At the moment, our intelligence agencies are collecting information and we are in direct talks with the Karnataka government. What is to be done next...I believe that within 24 hours, after all the information is collected, we will plan our next strategy," he said.
The home minister said that he has appealed to the Karnataka government that in a big city like Bengaluru, Close Circuit Television (CCTV) cameras should be installed at the earliest.
"If the state government faces any problem in installing CCTVs, and ask for assistance from us, then we are ready to provide them," he said.
"And in this regard, two of our senior ministers from Karnataka - Ananth Kumar (chemical and fertiliser ministry) and Sadanand Gowda (law and justice ministry) - met and gave details about the incident. Gowda went to the site and provided us with all information," he said.
"We will decide once we have all the information. The state and central intelligence agencies are playing a very active role at the moment and a final decision will be taken after consulting them," he said.
The central government is waiting for more details from the state. If needed, the case could be handed over to the NIA (National Investigation Agency), he said.
On being asked about the attack, he said: "At the moment, I cannot give a reason behind the attack and also the terrorist organisation behind it..."