Home Minister Gulabchand Kataria and Social Justice and Empowerment Minister Arun Chaturvedi are among the Cabinet ministers and Ministers of State who received the emails on December 22.
"We are examining the credibility and authenticity of the email and its sender who gave threats in the message saying 'You yourself understand what we will do'. We are investigating the matter and have collected inputs which are being shared with intelligence agencies," DGP Omendra Bharadwaj said.
He said that there is no specific target and also type of attack mentioned in the message which was sent on Monday purportedly by terrorists group Indian Mujahideen.
ADG-ATS Alok Tripathi said that language of the message was poor and no specific target was mentioned.
"The sender in a threatening language warns to be prepared," Tripathi said, while refusing to divulge further details of the emails received.
The home minister, who is in Udaipur, said that the DGP was aware of all the facts and that those behind the emails would be identified.
"We will ensure that full security is in place in the state and proper safety measures are being taken," Kataria told reporters.
The DGP said that the security arrangements have been further tightened in the state in the wake of the threat, which is being thoroughly examined.
"Alarming signals were coming for some time hence security arrangements were already tight and now other measures are also being taken from security point of view," he said.
However, he said, that there should be no panic.
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