Former West Bengal Chief Secretary Alapan Bandyopadhyay has received a death threat in a letter sent to his wife, PTI reported on Wednesday, citing the police.

“Madam, your husband will be killed,” the letter dated October 22 said, according to the police. “No body can save the life of your husband.”

The typed letter was sent on post to Bandyopadhyay’s wife Sonali Chakrabarty. The letter was signed by a person identified as Gourhari Mishra, who claimed to be working with the Department of Chemical Technology of Kolkata’s Rajabazar Science College, PTI reported.

The police have registered a complaint and are investigating the matter.

After retiring as the chief secretary of West Bengal government in May, Bandyopadhyay took over as a chief advisor to Chief Minister Mamata Banerjee.

He is facing disciplinary proceedings from the Centre on charges of “misconduct and misbehaviour”.

The proceedings were initiated after the West Bengal government refused to release him even as the central government’s Department of Personnel and Training asked him to report to its Delhi office.

The Centre’s order asking Bandyopadhyay to report to Delhi did not mention the reason for the move. But, it came hours after he and the West Bengal chief minister skipped a review meeting on Cyclone Yaas with the prime minister on May 28.