The French Consulate in Bangalore received a threat letter on 11 January apparently by al-Qaeda, said emerging reports.

Though a complaint regarding the threat letter was registered at the High Grounds police station in Bangalore on 14 January, the details came out only on Thursday. Priliminary investigation has discovered the Chennai address on the letter was fake.

The "intimidating" three-line letter asks French President Francois Hollande to cancel his visit to India for its Republic Day celebrations next week, reported PTI.

Hollande, who will arrive in Chandigarh on 24 January, is the chief guest at this year's Republic Day celebrations in New Delhi.

Meanwhile, security has been beefed up in New Delhi ahead of the Republic Day parade. Reports suggest over 70 skyscrapers near Rajpath will remain closed for security reasons.

There are also reports of terror alerts in Delhi, Mumbai and Kolkata ahead of Republic Day celebrations.

Indian intelligence agencies are working closely with France's Directorate General for External Security (DGSE) and the US' Central Intelligence Agency (CIA) to ensure foolproof security.