Amid a potential fresh threat, the Mumbai Police on Monday beefed up security for the family of industrialist Mukesh Ambani at his residence Antilia in south Mumbai, official sources said.

The move came after a taxi driver alerted the Mumbai Police after overhearing two suspicious persons who were reportedly collecting certain information on Antilia. Reportedly, the commuters were only asking questions about Antilia and no other place around it. There body language also appeared to be suspicious.

As per the police, the two commuters seated on a private cab but on checking it was found out that the vehicle number shared by the taxi driver does not exist.

The police have detained the taxi driver to record his statement, prepare a sketch of the two 'mysterious' persons, and scouring the CCTV footage of the route on which they commuted. Officials informed that the fact that Antilia was in the news earlier this year and Sachin Waze was arrested in the matter, alarmed the driver.

Road blocks have been erected at various strategic locations in Mumbai to help track the two unknown persons, who were reportedly carrying a couple of bags, as per the taxi driver's statement, though the police declined to share further details.