Ranchi, February 6 The Ranchi district collectorate received an email on Thursday threatening to blow up the premises, officials said.
The threat was sent to the Deputy Commissioner's official email ID, they said.
"An investigation is underway. Nothing suspicious has been found so far," said Ranchi Sub-Divisional Officer (SDO) Utkarsh Kumar.
A bomb detection and disposal squad (BDDS) has been deployed, and a search operation is being conducted across the premises, a police official said.
The cyber cell team has also been activated to ascertain the source of the email, he added.
On February 6, the Ranchi Civil Court also received a similar threat via email, which later turned out to be a hoax after a search operation found nothing suspicious, officials added.
