New Delhi, May 9 (PTI) The Special Protection Group(SPG) and the Intelligence Bureau(IB) were today ordered by the Government to take maximum precautions for Rahul Gandhi's security after an anonymous letter threatening to kill him surfaced.

The unsigned letter in Tamil threatening to kill the Congress Vice President at an election meeting in Puducherry was received by a senior Congress leader V Narayanasamy on May 5. Rahul is scheduled to address a rally of the Congress-DMK alliance tomorrow at Karaikal in Puducherry.

Acting swiftly, Union Home Secretary Rajiv Mehrishi directed the SPG, responsible for the protection of the Congress Vice President, and the IB to take all necessary precautionary measures in this regard.

Mehrishi's missive to the two agencies came soon after Union Home Minister Rajnath Singh asked him to take up the issue seriously and ensure protection to Rahul, official sources said.

Earlier, a delegation of top Congress leaders met the Home Minister and asked him to beef up Rahul's security following the assassination threat.

The team, including Ahmed Patel, Political Secretary to Congress President Sonia Gandhi; Treasurer Motilal Vohra and Congress Deputy Leader in Rajya Sabha Anand Sharma met Singh and apprised him about the threat to the Congress Vice President's life.

"The Home Minister has assured us of prompt action and security enhancement. He has also assured us that the agencies of the Centre and the states and SPG will be alerted about the threat that has been received," Sharma told reporters after the 20-minute meeting with Singh.

Narayanasamy, an AICC General Secretary and a former Union Minister, told PTI from Karaikal over phone that he had received an 'unsigned letter' at his Puducherry residence on May 5, threatening him and Rahul Gandhi.

He said the letter written in Tamil stated that "your party is responsible for closure of industries in Puducherry.

We will attack you and your former Prime Minister's son and will be blasted while attending the Karaikal meeting."

Narayanasamy said he had filed a complaint with police and had also informed the party high command.

The SPG guards the Prime Minister, the former Prime Ministers and their immediate family. Sonia Gandhi and her two children -- Rahul and Priyanka -- are SPG protectees.

Rahul's father and former prime minister Rajiv Gandhi was assassinated during a suicide bombing in Sriperumbudur near Chennai in Tamil Nadu on May 21, 1991 shortly before he was to address a Lok Sabha poll rally.