Chief Minister Devendra Fadnavis on Friday approved Z-plus security for social activist Anna Hazare, who received a threat note yesterday.
An FIR had been lodged at Parner police station in Ahmednagar district after the letter was received.
The letter read that a hired killer, who has a "habit of killing noble people," wanted to kill "social worker" Hazare for blood money.
Earlier this month, Hazare had received another threat letter that stated he would be "bumped off" if he does not dissociate himself from Delhi Chief Minister Arvind Kejriwal.