The CBI has filed a chargesheet against 20 people in a case related to the alleged killing of BJP worker Abhijit Sarkar in the post-poll violence in West Bengal in May, officials said on Thursday.

They have been accused of murder, and also charged under IPC sections related to common intention and destruction of evidence among other offences, they said.

Sarkar was brutally attacked by a mob on May 2 at his home in Calcutta, hours after curtains came down on the bitterly fought assembly elections with TMC recording astounding victory and the BJP emerging as the principal opposition in the state.

He was taken to hospital where he had succumbed to injuries. Hours before his death, he had reportedly posted a video on social media narrating the violence at his home.

Sarkar's family had refused to accept his body claiming it was beyond recognition.

It was only after DNA test, ordered by a court, which showed it was Sarkar's body that family accepted it earlier this month.

The CBI has filed its final report in the case before ACJM, Sealdah against 20 people: Sanjay Samanta, Samir Samanta, Sankar Das, Arun Dey, Rahul Dey, Sourav Dey, Sukhdeb Poddar, Amit Das, Arup Das, Biswajit Das, Sanjay Barik, Amit Das, Tumpa Das, Gopal Das, Papiya Barik, Sanjay Basak, Sufal Bose, Sanjay Dey, Abhijit Dey and Kajal Das.

It was alleged that the accused had attacked the victim with sticks and also broke the household articles of his house, CBI Spokesperson RC Joshi said.

The agency has kept the probe open, he said.