At least 300 schools in Italy were evacuated on Wednesday after receiving the same bomb alert message, the education minister said.
The security alert came amid rising concerns in Europe about so-called hybrid warfare threats which have targeted supermarkets, blood banks, air traffic and TV broadcasters.
Education Minister Giuseppe Valditara told the La7 TV channel that the alerts were presumed to be hoaxes, adding that the number of schools affected was expected to rise.
'Mikhail Andropov, leader of the Vilayat of Misoginistan'
"Following a nationwide bomb alert, we wish to inform you that all students have been taken to a safe area and remain under the supervision of teaching staff," one school in Rome informed parents through a messaging app.
The large number of schools affected "demonstrates how little credibility the threat has," Valditara said.
The email was signed "Mikhail Andropov, leader of the Vilayat of Misoginistan," according to a copy of the message seen by Reuters.
The same purported author claimed responsibility for email bomb threats sent on Friday to newsrooms in Ireland and Bulgaria.
Italian police forces are investigating the matter, a spokesperson for Rome police said.
No credibility in Italian schools bomb alerts, government source says
Checks carried out by Italian authorities show no evidence that bomb threats sent to schools across the country are credible, a government source said on Wednesday, calling the threats part of a strategy "aimed at generating alarm and concern."
Schools in N.Ireland sent threatening email but authorities believe not credible
Also on Wednesday, a large number of schools in Northern Ireland have been sent a threatening email, the Northern Ireland Education Authority said, but they have been advised to stay open as the authority said police did not regard it as a credible threat.
"The message has similarities with a bogus threat sent last month, which was declared a hoax by PSNI (police)," the Education Authority said.