An email allegedly threatening to blow up schools around 90 schools across Bengal, including Calcutta and Siliguri, sent the police into a tizzy on Monday.

Till late in the evening, neither the Calcutta Police nor the West Bengal Police issued any official statement on the threats. The schools in either of the cities would also not go on record about the threat.

The email was sent at 12.28 am, in the intervening night between Sunday and Monday by a user, “doll”, with the email id, happyhotdog101. A screenshot of the email with a list of more than 90 schools has gone viral, though the actual message has not been shared. It is believed that the sender had threatened bombs would be set off when the students arrive in the morning.

“The cybercrime cell was alerted about the email. Searches were carried out in the schools,” said a senior police officer.

The email was generated by an account linked to a Latvia-based email service provider, which was conceived in 2018 and started its operations in 2022, said police sources.

Last year on December 1, around 68 educational institutions in Bengaluru had received threat emails from an email id created from the same email service provider. Bengaluru Police had initially suspected the email to have originated from the Czech Republic or Slovakia.

It was later traced to the same end-to-end encrypted email service provider as in the Calcutta schools case, though the location was in Cyprus. According to news reports, responding to the Bengaluru Police, the email sender had used a Switzerland-based Virtual Private Network, which is also known for its end-to-end encryption and focus on privacy.

In June 2022, the Narendra Modi government, in a bid to tighten cybersecurity rules, had asked all VPN operators to store users’ data like names, email IDs, contact numbers and IP addresses for five years. They were also asked to share the data as and when asked by the Indian government. Most of the VPN companies refused to comply with the order and have removed their servers from India.

It is not known yet whether the Calcutta Police or the Bengal Police have reached out to the email service provider to probe Monday's threat mails.