BENGALURU: At least four private schools in Bengaluru on Friday morning received bomb threat emails, which turned out to be a hoax, police said.

An email titled "Bombs inside the school" was received by these schools at 7.24 am. The sender claimed to have placed several explosive devices within the classrooms of the respective schools.

"Hello. I am writing to let you know that I have placed several explosive devices (Trinitrotoluene) within school classrooms. The explosives are skillfully hidden, in black plastic bags," it stated.

The school authorities immediately alerted police, who reached the institutions concerned with the bomb disposal squads and anti-sabotage check teams, they said.

The students and staff were immediately evacuated from the school premises, police said, adding no suspicious objects were found.

"At least four schools in Central division (Bengaluru police) limits received a bomb threat email this morning, triggering panic. All necessary measures were taken as per protocol. Nothing suspicious was found and it turned out to be a hoax email," a senior police officer said.

Meanwhile, more than 20 schools in Delhi on Friday received bomb threats, triggering panic among the students and their parents.