Calcutta: Mamata Banerjee said on Monday that Aadhaar linkage was "very problematic", "dangerous" and against the right to privacy, referring to the purported leak of Aadhaar data on Internet.

The chief minister has been criticising the Narendra Modi government over making Aadhaar compulsory for schemes and benefits and has refused to link her Aadhaar to her cellphone numbers.

"Aadhaar linking is very problematic. In the name of Aadhaar, details are being given to websites. It is dangerous for freedom of expression and the country," she said.

"I cannot say why they did this. Some people feel happy even after doing bad things," Mamata added.

Mamata asserted that she was not against the system of unique identification, but was opposed to Aadhaar for possible leakage of information.

"I have PAN and voter card. But Aadhaar is dangerous because all personal information is given on websites," she said.

"Does Aadhaar mean that a person's personal details from head to toe would be public now? Telephonic conversations between a mother and a daughter, a husband and his wife are becoming public because of Aadhaar," she said at the state secretariat.

Leader of the Opposition Abdul Mannan echoed Mamata, claiming the Congress's stand on Aadhaar had been vindicated. "Prime Minister Narendra Modi should take moral responsibility and immediately resign," said Mannan.

CPM state secretariat member Asok Bhattacharya said the leak was proof that Aadhaar was not foolproof on data security.

But Bengal BJP president Dilip Ghosh accused those opposing Aadhaar of trying to cause "baseless panic".