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Premier John Hogan also says thick smoke and fumes have prevented officials from assessing the full extent of the recent damage.Orest Iwaszko/Albernin Charters/Supplied

Thousands of people in Newfoundland and Labrador’s capital city have been alerted to flee at a moment’s notice as out-of-control wildfires in the province are now threatening urban centres.

Crews are employing water bombers to slow the growth of flames in St. John’s, near the Trans-Canada Highway, where at least 20,000 residents are under evacuation alert as of Wednesday.

“It’s unnerving, really, because you don’t know. It’s living in the unknown,” said Olga Boland, who lives in Paradise, a suburb in the city close to the fire.

Where in Canada are there wildfire smoke warnings? Our map tracks air quality across the country

Much of Ms. Boland’s neighbourhood has been mandated to leave their homes, while other parts have been asked to be prepared for emergency orders. “It’s an uncomfortable feeling,” added her sister-in-law Patty Boland, as the two of them shopped at a Costco on Danny Drive, an area that is also under alert.

“We’re not in the area where we are being so badly affected. But when I think about the areas of Newfoundland that are being devastated, it’s absolutely heartbreaking. It’s just terrible.”

Earlier in the day, Premier John Hogan told reporters at a briefing that four other significant wildfires in the province are continuing to destroy homes and properties, the largest of which has reached about 6,400 hectares in size.

He said thick smoke and fumes have prevented officials from assessing the full extent of the recent damage.

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A water bomber drops water onto a wildfire burning in the Paddy’s Pond area just outside St. John’s, on Wednesday.Elling Lien/The Canadian Press

With forecasts showing heavy winds, extreme heat warnings and dry conditions, Mr. Hogan said fire behaviour is expected to remain hazardous in the coming days. That applies to “almost the entirety of the province right now,” he added.

“As this continues to get worse over the last few days, it’s very clear that all Newfoundlanders and Labradorians’ level of anxiety continues to rise,” the Premier said Wednesday.

“There is a lot happening. There is a lot of serious, hard, dangerous work being done.”

Canada has been experiencing some of the most destructive wildfires in recent decades this summer, adding up to a season that is on track to be the worst on record in terms of area burned, second only to 2023.

Yumna Iftikhar is special to The Globe and Mail