The Army Public School in Delhi Cantonment received a bomb threat email on Monday, prompting security agencies to launch a search operation on the premises, a Delhi Fire Services official said. The school administration informed the authorities in the morning after receiving the mail that warned of an explosive device planted on the campus. "We are verifying the source of the email. So far, nothing suspicious has been found. As a precautionary measure, a thorough search operation is underway on the school premises, which has been vacated," a senior police officer said. The cyber cell has been roped in to trace the origin of the email and identify the sender, he added. Teams from Delhi Police, bomb disposal squad, dog squad and fire department are on the spot, the officer said.