Ontarians received emergency alerts on their cellphones, radios and TVs at 2 p.m. Friday, warning recent travellers to stay at home.

"You are at high risk of spreading COVID-19. You are required by law to self-isolate for 14 days," the alert reads.

"Do not visit stores, family or friends. Everyone should stay home to stop the spread."

Health Minister Christine Elliott says Ontario is using every tool to ensure people are well informed about the steps they should take.

The federal government recently passed an order requiring people arriving in Canada by land, air or sea, to self-isolate for 14 days, with penalties of up to $1 million or three years in prison.