PRAGUE (Reuters) – Thousands of Czechs returning from holidays in Italy will have to go into quarantine for two weeks or face fines as part of efforts to curb the coronavirus, health officials said on Friday.

Eighteen cases have been reported in the Czech Republic, all of them people who have traveled to Italy – Europe’s worst-hit country – or who have come into close contact with those travelers.

“We clearly told our people not to travel to Italy and we clearly said that everyone who is returning from Italy will go into quarantine, under the law,” Prime Minister Andrej Babis told a news conference.

The health ministry said around 16,500 Czech residents were currently in Italy, where many families go on ski trips during winter school breaks.

It said anyone returning after March 7 should phone a doctor who will put them in quarantine at home, unless they need hospital treatment.

Anyone breaking that quarantine could be fined up to 3 million crowns ($134,156) under the country’s Public Health Law, the ministry added.

The Czech Republic reported six new cases on Friday, its biggest daily jump since its first positive tests on Sunday.

The government has already barred flights from northern Italian cities including Milan or Venice, and banned spectators from turning out to watch an international biathlon race in the southeast his weekend.

The health ministry this week stopped the export of respirator masks and hand disinfectants, among other health products.

(Reporting by Jason Hovet and Robert Muller; Editing by Alex Richardson and Andrew Heavens)