The Congress demanded a probe into the allegations, with former prime minister Manmohan Singh saying it is not a "good omen".
"If ministers' houses are bugged, then it is not a good omen. It should be investigated. How can it happen? It should be explained by the government in the house," the former prime minister told reporters at an Iftar get-together hosted by Congress president Sonia Gandhi Sunday. BJP spokesperson Mukhtar Abbas Naqvi asked why Manmohan Singh was quiet when bugging was reported in then finance minister Pranab Mukherjee's office. "Why was Manmohan Singh quiet when there were reports of bugging of his ministers," Naqvi asked. BJP leader Subramanian Swamy questioned if former Congress-led United Progressive Alliance (UPA) government was responsible for the bugging. He said that the bugging took place around October last year "when the UPA was in power, the NSA has specifically targeted the BJP and Gadkari was a very important person. He had the confidence of the RSS". Congress leader Manish Tewari said: "If the BJP feels it is to be blamed on UPA, they should get it probed."