New Delhi, Aug 7 (IANS): Supreme Court judge Justice Dipak Misra, part of a three-member panel that had rejected 1993 Mumbai serial blasts convict Yakub Memon's mercy plea, has received a threat letter, police said on Friday.

Misra received the letter at his New Delhi residence after which he lodged a complaint at the Tughlaq Road police station.

Memon was hanged on July 30 after the apex court bench comprising Justice Dipak Misra, Justice Prafulla C. Pant and Justice Amitava Roy post-midnight rejected Memon's plea seeking 14 days' time before the execution of his death sentence.

"We have registered a case on the basis of the judge's complaint. We are scrutinising the letter to verify its authenticity. We are also finding out if its a prank played by someone or is circulated by the associates of Memon," police sources told IANS.

Senior police officials could not be contacted for a comment despite repeated attempts and some of them denied commenting saying "it is a very sensitive matter and is under probe".