The security of Assam Chief Minister Himanta Biswa Sarma has been tightened after a voice message issuing threat to him was received by a number of Assamese journalists based in Delhi and Assam on Sunday from a person identifying himself as Gurpatwant Singh Pannu from the banned Sikhs for Justice.

Officials in the know claimed that the voice in the message was that of Pannu, who has been designated as a terrorist under the stringent anti-terror law -- Unlawful Activities (Prevention) Act -- by the Union Home Ministry. He is at present in the United States.

The caller claimed that Sikhs were being "tortured" in Assam jail and asked Sarma to desist from it.

After the March 18 crackdown on pro-Khalistan radical preacher Amritpal Singh, the Punjab government had shifted seven of his close aides to Assam's Dibrugarh jail after slapping them with the National Security Act.

The voice message, which was received twice by some of the journalists in the afternoon, came from masked Indian phone numbers.

Acting promptly, the Assam Police said it has taken the threat to Sarma seriously and his security has been "adequately sensitized to the emerging threat" and a case has been registered.

Director General of Assam Police G P Singh tweeted: "Reference audio clip threatening Hon CM Assam by a person called Gurpatwant Singh Pannu, a designated individual terrorist under Indian law and heading an unlawful association called Sikhs for Justice: A case under appropriate sections of IPC and UAP Act has been registered at STF Police Station of Assam; the security component of Hon CM has been adequately sensitized to the emerging threat." "In view of global events, the threat is being taken very seriously by Assam Police. The central agencies have been kept in the loop on the issue," the DGP tweeted.

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