"A conspiracy has been hatched to kill Mukul da and Arjun Singh. The conspiracy is continuing," he said at a sit-in demonstration here.
Both Roy and Singh were earlier with the state's ruling Trinamool Congress. While Roy joined the BJP in 2017, Singh crossed over to the saffron camp in March 2019, ahead of the Lok Sabha polls.
Vijayvargiya accused the Trinamool of carrying out a politics of vendetta By filing false cases against BJP leaders.
"You will be surprised to know since Mukul da joined BJP, 32 cases have been slapped against him. When he was not in the BJP, then everything about him was fine. Now there are even murder, attempt to murder and many such cases against him.
"Till day before yesterday, 50 cases have been lodged against Arjun Singh. And all these cases have been filed in the last six months that he has been with us," he said.
Vijayvargiya said he hasn't been spared too. "There are cases against me also. Some of these cases are such I find it abominable to even mention them. There are even children trafficking cases against me."
He also expressed surprise over Chief Minister Mamata Banerjee sitting on a dharna earlier this year after CBI sleuths went to then Kolkata Police Commissioner Rajeev Kumar's residence to question him on issues related to Ponzi scam. Kumar headed the special investigation team constituted by the Banerjee government to probe the scam till the Supreme Court handed the matter to the CBI.
"When CBI arrested senior Trinamool functionaries, you didn't do anything. But you sat on a dharna for Kumar.
"You did that because he is in possession of documents about your wrong-doings related to the chit fund scam. He is now blackmailing you. You have to do whatever he wants you to do, " he alleged.
The BJP has organised the sit-in demanding arrest of the guilty in the Sandedhkhali killings in June. At least three people, two of them BJP activists and another Trinamool worker, died in the clash between the two parties in the remote area of South 24 Parganas district.
( With inputs from IANS )