Rubbish, the Trinamool said, predictably. What was not predictable: even Bengal's home secretary stepped up to rubbish the charge against Abhishek Banerjee as baseless.
Mukul Roy's salvo against Abhishek Banerjee was on three counts - that he was owner of a company that printed all of Trinamool's posters, banners and placards and a company that ran Trinamool's mouthpiece, 'Jago Bangla'.
The third charge drew the loudest applause from BJP supporters. "You saw the football world cup was sponsored by Biswa Bangla. Now, Biswa Bangla is not a government concern. I have the papers," Roy said, holding up a sheaf, and added, "Biswa Bangla is a private company and its owner is Abhishek Banerjee. It is registered at 30B Harish Chatterjee Street."
That address is the home of the chief minister and her family.
Some hours later, Partha Chatterjee, the secretary general of Trinamool and one of the senior-most ministers in government, held a press conference to dismiss Mukul Roy's claims.
"He is speaking rubbish," Mr Chatterjee said. "This is nothing but gaddari (betrayal) but Trinamool workers and leaders are united. No question of Roy targeting anyone, he is our target, he has become the people's target," he added.
Mukul Roy had also attacked Mr Chatterjee as someone who organized Durga Pujas with funds donated by Ponzi companies.
What was unusual, however, was, even before Mr Chatterjee's press meet, the state's second senior-most officer, the home secretary, met the press to clarify the Biswa Bangla issue.
"We have come to know that at a public rally, Mukul Roy has said the Biswa Bangla brand is Abhishek Banerjee's personal property. That is totally wrong, baseless. The Biswa Bangla logo and brand was created by the chief minister originally and she has willingly given to the West Bengal government and is registered with it."
Mamata Banerjee, too, struck a note of defiance in response to Mr Roy's opening barbs in his speech at Rani Rashmoni in the heart of Kolkata that was attended by about 20,000 people.
"In 2006, people were dying and Buddhadeb Bhattacharjee was opening a film festival. In 2017, people are dying in Bengal of dengue - 80 to a 100 of them - and Mamata Banerjee is getting ready for 'naacha, gana' and the film festival. That Mamata Banerjee is a changed person today," Mr Roy said.
Ms Banerjee said, "Some people are saying, why should a film festival be held. Why should it not? Should we stop holding Durga Puja also? Politics is not about jhanda only but also culture." She also defended the fact that she was traveling abroad later tonight. Mr Roy alleged that Ms Banerjee didn't travel alone.
So was it all hot air or hot stuff?
Ever since Mukul Roy joined BJP a week ago, Trinamool maintained pin drop silence on his exit. Hot air or hot stuff, today that silence was broken.