RJD leader from Bihar Shivanand Tiwari has called the Maoist threat to Prime Minister Narendra Modi a planted story to garner sympathy votes.

"Maoist threat to PM is a planted story to garner sympathy votes as PM's graph is declining fast," said Shivanand Tiwari, RJD Vice President.

Calling it "Modi's old tactic", Congress, too, expressed similar views and demanded a probe into the matter.

"I am not saying this is completely untrue but it has been PM Modi's old tactic, since he was CM. Whenever his popularity declines, news of an assassination plot is planted. So it should be probed how much truth is in it this time," said Sanjay Nirupam, Congress.

ALSO READ | Plan to assassinate Narendra Modi in 'Rajiv Gandhi-type incident' intercepted

Earlier, India Today TV accessed a letter describing a plan to assassinate Prime Minister Narendra Modi in a "Rajiv Gandhi-type" incident, which a leading daily said was "gathered from material seized" from five people arrested for "alleged Maoist links".

Pune police claim that the letter - written on April 18 by "R" to one "comrade Prakash" - described a plan to assassinate the Prime Minister.

The message does not explicitly say the plan is to assassinate Modi, but its implication is clear. It says the "Modi-led Hindu fascist regime" is "bulldozing its way into the lives of indigenous adivasis".

"In spite of big defeats like Bihar and West Bengal, Modi has successfully established BJP government in more than 15 states. If this pace continues, then it would mean immense trouble for the party on all fronts. Greater suppression of dissent and more brutal form of Mission 2016 (OGH)."

"Com. Kisan and [a] few other senior comrades have proposed concrete steps to end Modi-raj. We are thinking along the lines of another Rajiv Gandhi type incident. It sounds suicidal and there is a good chance that we might fail, but we feel that the party PB/CC must deliberate over our proposal," the letter read.

"Targeting his road shows could be an effective strategy," the letter says. "We collectively believe that [the] survival of the party is supreme to all sacrifices. Rest in the next letter."

Rajiv Gandhi, India's sixth prime minister, was killed in 1991 in Sriperambudur, a town in Tamil Nadu, by a suicide bomber. He was scheduled to address an election rally.