Mumbai Police have stepped up security and launched an investigation after an e-mail warning of bomb attacks at four prominent locations in the city, including Bollywood actor Amitabh Bachchan's residence, Jalsa, the Bombay High Court and the Bombay Stock Exchange (BSE).

The threat message, received by the Bombay High Court, also named the Worli Racecourse as a potential target. Security agencies have been alerted, while police teams are working to trace the person behind the e-mail and establish the credibility of the warning.

The latest incident has brought Bachchan's security back into focus, marking the second threat in recent weeks in which the veteran actor has been named.

On October 22, an e-mail threatening attacks was sent to a Mumbai school, with Bachchan's name figuring in the message. Investigators had subsequently clarified that the actor had not received any direct communication threatening him.

The earlier incident had also led to changes in the actor's public appearances. During his customary Sunday interaction with fans outside Jalsa on November 1, Bachchan greeted visitors from behind a protective glass barrier. His son, Abhishek Bachchan, was also present beside him.

The unusual security arrangement prompted the All Indian Cine Workers Association to approach Prime Minister Narendra Modi, seeking intervention over concerns surrounding the safety of actors and their families.

CELEBRITIES FACE A SERIES OF THREATS

The latest bomb warning comes against the backdrop of several security-related incidents involving Bollywood personalities.

On October 18, unidentified assailants opened fire at actor Tiger Shroff's BMW in Mumbai. The Lawrence Bishnoi gang subsequently claimed responsibility for the attack, adding to concerns over threats directed at members of the film industry.

The situation escalated further this week when actors Tusshar Kapoor and Ayushmann Khurrana received threatening messages allegedly sent in the name of the Bishnoi gang.

Mumbai Police arrested a 30-year-old Bengaluru-based IT professional on Wednesday in connection with the threats against the two actors. The Mumbai Crime Branch is investigating the case.

Initial findings have not established any connection between the arrested man and the Lawrence Bishnoi gang. Police are also examining the authenticity of the threatening audio messages and the claims made by their sender.

With the latest e-mail naming prominent public institutions alongside Bachchan's residence, investigators are examining the threat while security agencies remain on alert across the city.