A bomb scare, triggered by a hoax call, spread panic at Sri Ramakrishna Sikshalaya, in Howrah’s Bantra, moments before unit tests were to start on Thursday afternoon.

A two-hour search by police and a team from the district intelligence branch yielded nothing.

An anonymous caller asked the head teacher around 1pm to cancel the unit tests, as bombs planted in a classroom would explode any time.

The tests, however, were held as scheduled.

The managing committee of the school claimed the hoax call was “part a conspiracy of certain vested interests bent on disrupting the functioning of the school”.

Tapan Kumar Ghosh, the head teacher, said: “I got a call around 1pm. The caller told me that bombs were planted in a classroom and that I must cancel the unit tests and ask the students to leave immediately. I asked him to disclose his identity, but he hung up.”

Ghosh alerted Bantra police station, a few yards from the school.

Though the students were not informed about the call, they got wind of it, seeing cops swooping down on the campus with metal detectors.

Many called their parents, saying bombs had been planted in the school. Several parents rushed over and waited anxiously for the search to end.

Anik Roy, a Class IX student, said: “A senior told me that bombs have been found in one of the classrooms. I rushed out of the premises and called my father.”

Ranjan Kumar Chongder, the school secretary, said: “The culprit should not go unpunished. We will ask BSNL to identify the caller. As soon as he is identified, we will lodge a complaint against him. We have also decided to install a Caller Line Identification machine on our telephone.”