HALIFAX — Nova Scotia's top health official has revoked a special exemption for workers at Halifax-based Irving Shipbuilding that allowed them to travel to and from the United States during the pandemic.

Dr. Robert Strang, chief medical officer of health, issued a statement Wednesday saying questions and concerns have been raised about the exception granted in June by the province's public health department.

He said "very tight restrictions" were placed on the exemption, which he approved. He did not offer details about the nature of the concerns that were raised.

Strang, however, made it clear there will be no further company travel to or from the United States while the border between the two countries remains officially closed for non-essential visits.

He also said he has ordered some Irving employees to isolate themselves at home for 14 days and submit to COVID-19 testing.

Meanwhile, Nova Scotia reported one new case of COVID-19 Wednesday.

Authorities said the case was identified Tuesday and involves a truck driver who travelled outside the country as an essential worker. The province currently has five active cases of the novel coronavirus.

Also on Wednesday, the Nova Scotia Health Authority issued a warning to travellers who were aboard an Air Canada flight from Toronto that arrived in Halifax on June 26, saying passengers could have been exposed to COVID-19.

Air Canada flight AC 626 departed Toronto at 8:15 p.m. and landed in Halifax at 11:17 p.m.

Health officials said anyone on the flight could have been exposed to the virus, but added an investigation has indicated that passengers in rows 29 to 23, and in seats A to C, were more likely to be at risk.

Passengers in those seats are being asked to call 811 for advice.

Anyone exposed to the novel coronavirus on the flight may develop symptoms up to and including July 10.

This report by The Canadian Press was first published June 8, 2020.

The Canadian Press