Thousands of students have been evacuated from nearly 100 schools in and around India's capital Delhi after fake bomb threats were emailed to them.
Authorities say the threats appear to be a hoax. Nothing was found during a search of the schools, they add.
Police say they have traced the origin of the threat emails and an investigation is under way.
The federal home ministry and Delhi Police have asked people to stay calm.
Delhi's Lieutenant Governor VK Saxena, the constitutional head of the state, said schools in Delhi and neighbouring suburbs that received the bomb threat have been cordoned off as search operations are being carried out.
The city's Fire Services said they sent fire engines to the schools but found nothing during their search.
"Dog squads, and bomb disposal units are also working," Mr Saxena told local media. "I want to assure the people of Delhi that Delhi Police is fully prepared and we will try to prevent any untoward incident from happening."
On X, formerly Twitter, Mr Saxena posted a message asking parents not to panic and to co-operate with the administration "in ensuring safety of schools and the children".
A senior Delhi Police official told reporters that some hospitals in the capital had also received similar letters on Tuesday.
Suman Nalwa, a public relations officer with the police, said that it seemed "someone had done this to create panic".
"Nothing untoward has been found so far," she told ANI news agency.
Delhi's Education Minister Atishi said the government was in touch with the police and schools and was constantly monitoring the situation.
