Congress leader Sam Pitroda's smartphone, laptop and server have been repeatedly hacked over the past few weeks with hackers issuing threats and demanding tens of thousands of dollars in cryptocurrency, according to a mail sent to those on his mailing list.

"They have warned that, if unpaid, they will launch a smear and misinformation campaign to tarnish my reputation by contacting people in my network," Pitroda said in the email.

"I want to bring to your attention a critical matter: my laptop, smartphone, and server have been repeatedly hacked and severely compromised over the past few weeks," it read.

In the email addressed to family and friends, the Indian Overseas Congress chief urged them "not to open" any emails or messages that appear to be about him from any unknown mail ID or mobile number, not to click on any links and not to download any attachments.

He added that these might contain malware that could compromise their devices.

Pitroda further said that he was travelling but planned to take immediate action upon his return to Chicago.

"This will include replacing outdated hardware, upgrading software and implementing robust new security measures to safeguard my digital presence. I sincerely apologise for any inconvenience or concern this situation may cause. Thank you for your understanding and vigilance," he said in the email.

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