Police arrested Samir Debnath, 30, who on Sunday night went to the office and targeted Health and PWD Minister Chaudhury and Transport and Power Minister Dey.
Samir Debnath initially told the ministers that his father was critically ill and he needed money for his medical treatment. The claim was found to be untrue, a police official said.
Debnath's family is known to support the Communist Party of India-Marxist.
During the incident, Chief Minister Manik Sarkar and CPI-M leaders Bijan Dhar and Gautam Das were at the party office.