There is no evidence to verify whether Buddhadev Bhattacharya had commented on Madrasas, calling them "breeding ground for anti-national activities."
However, later the former Left Front chairman Biman Bose clarified on behalf of Bhattacharjee. Bose termed the media reports as "inaccurate" and said that the CM was "misquoted" by the media. While speaking to the press, Bose said that the CM had only "appealed" the unaffiliated madrasas to be in the mainstream so that their students can go for higher studies, the Times of India reported.
Later, in 2016, the Bengal BJP demanded an "immediate sealing" of the Indo-Bangladesh border, alleging that madrasas operating along the border were funded by foreign countries and had become a breeding ground for terrorism and anti-national activities in the country.
The statement was made by the party's state president Dilip Ghosh, saying, "madrasas are creating a chain, which is making the Indo-Bangla border vulnerable to anti-national activities, illegal cattle trade, and smuggling." Ghosh further quoted the former CM Buddhadeb, saying, "A few years ago, the then chief minister Buddhadeb Bhattacharya had said that madrasas in bordering areas of West Bengal are breeding grounds of fundamentalism. But later on, he had retracted his statement due to pressure from his party". Adding that one can't take a CM's comment lightly, Ghosh said, "Whatever he had said was based on reports of IB and police", the India Today reported.
According to the Ministry of Home Affairs, as of 2017, more than 25,000 active voluntary organizations, including schools and madrasas, have received assistance from foreign countries.
However, there is no conclusive evidence to show whether former Chief Minister Bhattacharjee had made the statement over West Bengal's madrasas. Thus, the claim is unverifiable.