The body which was kept in the police morgue at the Burdwan Medical College, was handed over to Karim's father and his cousin Amirul Hossain after identification, police sources said.
Hossain told newsmen present at the hospital that they had identified the blast accused to be Karim from his photos published in the papers.
Karim had left his home in Kafirpur village in Kinnahar in neighbouring Birbhum district about two and a half months before the Khagragarh blast on October 2 and had gone off to Kerala. He had not maintained any relations with his family since his departure, Hossain added.
The body would be taken to Kafirpur where the last rites would be performed, Hossain said.
Apart from the four member NIA team, the Burdwan police station Inspector-in-charge Abdul Gaffar and Sub-Inspector, who was the first Investigating Officer, Akash Munshi was present during the handing over of the body.
The body of the other accused, Shakil Gazi alias Shakil Ahmed, who was also killed in the blast is yet to be claimed, police said.
It is suspected both had links with banned terror group Jamaat-ul-Mujahideen Bangladesh (JMB).