The CBI has sought income-tax details of Birbhum district Trinamul Congress president Anubrata Mondal in connection with its probe into alleged multi-crore cattle smuggling case.

Mondal, who was supposed to appear for another round of questioning before a CBI team in Calcutta on Tuesday, informed the agency that he was unwell and had been advised rest by doctors. His lawyers informed that Mondal would extend his cooperation to the agency after a fortnight.

CBI officers said they wanted to check the documents that Mondal had submitted with IT returns to understand if the Trinamul heavyweight had benefited from the alleged cattle smuggling.

Mondal had returned to Birbhum on Friday, one-and-a-half months after he had left for Calcutta where he had appeared before the CBI for a round of questioning in the cattle smuggling case.