A day after the North Block received a hoax bomb threat email, the Delhi Police on Thursday wrote to Google seeking details of its IP address, an official source said.

The Internet Protocol (IP) address is a unique identifying number assigned to every device connected to the internet.

A bomb threat on Wednesday sent alarm bells ringing in the North Block, which houses the office of the Ministry of Home Affairs (MHA), but was declared a hoax after nothing suspicious was found.

A letter has been sent to Google to provide the IP address of the email which was sent to the MHA office, an official source said.

The Delhi Police Special Cell and the local police are investigating the case. A case may be registered at Kartavya Path police station for further investigation, an officer said.

A senior officer posted at MHA received the threat through an email around 3:30 pm on Wednesday. The email stated that the "building will explode as a bomb is planted".

The mail was sent from an anonymous Gmail address and it is suspected that the sender used a VPN (virtual private network) that masks the IP address, according to police.

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