"We received the mail on Saturday. It was received at his official e-mail address," the Chief Minister's public relations officer Sukanta Panda said.
According to officials, the mail refers to bullet injuries to top Maoist leaders Kishenji and Bikram.
"We will reply to each bullet that hit Kishanji and comrade Bikram," said the e-mail sent by the Central Military Commission (CMC) of the Peoples' Liberation Guerrilla Army (PLGA), a Maoist outfit.
"As soon as you launch joint special operation or 'Green Hunt', we will start attacks at Bhubaneswar, Cuttack and Puri simultaneously," the e-mail has said.
Asking the chief minister not to rejoice over the deployment of central para-military force (CPMF) in the state, it said, "Your happiness over getting additional force is temporary."
This is the third vicious e-mail received by Patnaik this year.
A similar mail was received on the eve of Republic Day. He had also received a vicious mail from the official e-mail account of newly-formed Central University of Orissa at Koraput in Feb 2010.