The specimen was found on the south-eastern bank of Bagjola canal in Bhangar’s Krishnamati village, following the interrogation of Mohammad Siyam Hussain, a key suspect in the case who was arrested by the Nepal Police and extradited to India, he said.

"The bone parts appear to be of a human being as suggested by medical officers and forensic experts who were present when these were recovered," the CID officer said.

It has lodged a suo moto case in this regard at the Bijoyganj Bazar Police Station, he said. The bone parts will soon be sent for forensic examination.

"Search is underway to trace other body parts of the Bangladeshi politician,” the officer said. Sleuths of the CID had earlier recovered pieces of flesh, weighing around 3.5 kg, from the septic tank of a flat in New Town area where the MP was last seen on May 12.

The daughter of the Bangladesh MP is likely to arrive in Kolkata next week to take part in a DNA test in connection with the recovery of the bones and flesh pieces, the CID officer said.

A key suspect in the case, Hussain was arrested by the Nepal Police and extradited to India on Friday. He was also taken to the New Town flat on Sunday to assist the CID in tracing the body parts of the Bangladesh MP, and the tools used to commit the crime.

Hussain was brought to West Bengal on Saturday evening and sent to 14-day custody of the CID by a local court in Barasat in North 24 Parganas district. An initial probe had revealed that the MP's close friend Akhtaruzzaman, a US citizen, paid around Rs 5 crore to those involved in the crime.

Akhtaruzzaman has a flat in Kolkata, and is probably in the US at present, CID officers had said.

Circumstantial evidence indicated that the Awami League leader was first strangulated and killed after which his body was chopped into pieces, police claimed.

Efforts to locate the missing MP, who reportedly arrived in Kolkata on May 12 for medical treatment, have been underway since Gopal Biswas, a resident of Baranagar in north Kolkata and an acquaintance of the Bangladeshi politician, filed a complaint with the local police on May 18. Anar had been staying at Biswas' residence upon his arrival.

In his complaint, Biswas mentioned that Anar left his Baranagar residence for a doctor's appointment in the afternoon of May 13 and was expected back home for dinner. However, Anar's disappearance prompted Biswas to file a police complaint.