Security around the office and home of Union Minister for Road Transport Nitin Gadkari was tightened following extortion-cum-death threats, officials said here on Saturday.

At least three calls were received by Gadkari's private office in the city - between 11.30 a.m. - 12.30 p.m. - and the caller purportedly uttered the name of absconding mafia don Dawood Ibrahim Kaskar.

The unknown caller reportedly made extortion demands and issued death threats targeting Gadkari - who is currently in Nagpur for the Makar Sankranti festival -- before disconnecting abruptly.

The Minister's office staff immediately informed the local police and senior officers, along with their teams, have reached there to investigate.

Further details like the caller's identity and their antecedents are awaited.