Social activist Anna Hazare has received a threat letter which states that he will meet the fate of rationalist Narendra Dabholkar if he continued to support Delhi chief minister Arvind Kejriwal and his deputy Manish Sisodia.
It also asked the Gandhian to stay put in his native village, police said.
Office of Hazare in Ralegan Siddhi registered a formal complaint at Parner police station on Tuesday.
The letter which was received by Hazare's office three days ago is written in English, Hindi and Marathi.
"It is a handwritten letter and we are unable to see postal stamp properly to trace out its origin", sources in Hazare's office said. It has been handed over to the police for further investigation.
Hazare, who is currently at Rohtak in Haryana to kick off his campaign against land acquisition bill and 'one rank one pension' (OROP), has already been provided 'Z' security.
Sources in Hazare's office also said that Maharashtra Police have alerted their counterparts in Haryana after receiving the complaint.
Hazare has received threatening letters in the past but government provided him security after Pansare's killing in February this year. A permanent police troop is deployed in his village. The police had also asked the social activist to shift to a safer place.
Hazrae had met Kejriwal and Sisodia at Delhi's Maharashtra Sadan last month and told them that Prashant Bhushan and Yogendra Yadav should not have been expelled from the party, suggesting that there should be reconciliation as the two are "old colleagues".