Congress member Asit Mitra asked about the progress of Rajiv Gandhi Gramin Vidyut Yojana in the state when the lights went off as soon as Gupta stood up and started to answer.
Congress members, who entered the house wearing helmets, but removed them on the Speaker's insistence, then staged a walk-out and the Speaker adjourned the House for a brief period.
On congregation after the adjournment, Parliamentary Affairs and Industry minister Partha Chatterjee said there was something fishy about the incident since the assembly was given dedicated power supply. He urged the Speaker to order a probe into the matter which was immediately conceded.
Banerjee asked the special secretary of the assembly to inquire into the incident and submit a report in seven days.
The Congress members again staged a walkout when an adjournment motion on higher power tariff charged by the West Bengal State Electricity Distribution Limited moved by them was not allowed for a discussion.