Nothing suspicious has been found after police received a threat that bombs were placed at a number of schools on the small Canadian province of Prince Edward Island.

Royal Canadian Mounted Police Sergeant Kevin Bailey said the threat came via fax on Wednesday morning, and that schools on the normally sleepy island were notified within 10 minutes. More than 19,000 students were evacuated.

"There's been no threat found. Everybody is safe," Mr Bailey told reporters.

The threat was faxed to Royal Canadian Mounted Police in Canada's capital of Ottawa, Mr Bailey said.

"The message stated that the bombs had placed at a number of schools and would be detonated today," Mr Bailey said.

A suspect has not been identified, he said.

Students at more than 60 English language and French language schools were taken to safe locations by staff outside the schools, where buses met them.

Mr Bailey said bomb threats are hard to evaluate for credibility, but said authorities like to they err on the side of caution. "This disrupts a lot of lives," he said.

Parents and guardians were asked to wait for further instructions before picking up their children.

Parker Grimmer, the island's director of public schools, said police contacted the school system on Wednesday morning about "a threat that was of a significant nature" and asked for the evacuation of all schools. He said he expects all students to return to classes on Thursday.

"This is new to us so we are reacting in a new way," Mr Grimmer said. "But we have plans and procedures and I think we followed them."

At Holland College in the provincial capital of Charlottetown, a woman burst into the classroom to tell everyone to pick up their books and evacuate immediately, student Morgan McNeil said. Outside, everyone was in a panic and helicopters were flying overhead, he said.

"I know there will be a process to look at this afterward but we wanted to ensure the safety of those students," Mr Grimmer said. "This is not a normal day and this is a day that I think we responded to well."

Mr Bailey said similar threats were made to schools and colleges in the nearby province of Nova Scotia, where the NSCC Marconi Campus, Cape Breton University and the NSCC technology campus in Halifax were evacuated.

At least one school in the United States also was threatened, he said. It was not immediately which one was involved or if it was evacuated.