Bangladeshi MP Anwarul Azim Anar was smothered with a pillow soon after he entered a flat in New Town near here, an official of West Bengal CID claimed on Wednesday.
Arrested accused Mohammad Siyam Hussain who was arrested in Nepal, admitted during interrogation that a woman also helped others in strangulating the Bangladeshi politician, he added.
The woman was stated to be the girlfriend of Akhtaruzzaman, a US national and allegedly the prime accused in the case.
"After killing the MP, they chopped his body into several small pieces, put them into plastic bags and then dumped them off in several parts of New Town, Bagjola canal before fleeing to different hideouts," he told PTI.
He has also claimed that some parts of the body were put into the trolley suitcase and then dumped somewhere near the Bangaon border with Bangladesh, he claimed.
The sleuths continued their search operations for the body parts, he added.
The state CID recovered on Sunday parts of human bones near a canal in South 24 Parganas district after interrogating Siyam, who was arrested by the Nepal Police and extradited to India.
Besides, the CID officers were grilling both and the butcher, who had cut the body, in connection with the probe, he added.
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 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.
Efforts to locate the missing MP, who reportedly arrived in Kolkata on May 12 for medical treatment, had begun after 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.
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