Updated July 22, 2023 at 2:52 PM ET

Heavy, relentless rain swept through the southeastern tip of Canada — flooding roadways, knocking off power and forcing residents to evacuate their homes as officials feared a dam might be breached.

The excessive rain in Nova Scotia comes weeks after the province was engulfed by Canada's unprecedented wildfire season. Four people have been reported missing, two adults and two children.

A Royal Canadian Mounted Police spokeswoman said two children went missing after the vehicle they were travelling in got stuck underwater, while the three other occupants were able to escape safely. Two other people, described as a youth and a man, remain missing following a separate vehicle submersion.

"Some of the same residents that were impacted by the wildfires are now dealing with the flooding," Halifax Councillor Lisa Blackburn told NPR.

The downpour began in Nova Scotia on Friday. As of Saturday morning, parts of the province had already accumulated nearly six inches of rain. In some areas, rain fell over an inch per hour.

"The ground, already near saturation, has little ability to absorb further rainfall," Environment Canada wrote in a statement.

Central and eastern Nova Scotia is forecast to receive between 1-4 inches of more rain on Saturday. The storm is expected to last until late afternoon in central Nova Scotia and late evening in the eastern regions.

As of Saturday morning, over 18,000 households were without power according to Nova Scotia Power.

The Nova Scotia government issued an evacuation order for people living near the Saint Croix River system due to concerns that a nearby dam may soon overflow. Residents living along Mersey River have been asked to prepare for a possible evacuation.

In Halifax, the capital of Nova Scotia, multiple roads were closed off and people were urged to avoid driving as a result of flash flooding.

Blackburn said preliminary reports tally about 150 homes in Halifax were damaged by the flood, and she expects that number to keep growing.

"Numerous roads are washed out & remain closed due to flooding. There are abandoned cars on roads & highways causing dangerous conditions," the Halifax Regional Municipality wrote on Twitter.

Search and rescue teams were deployed by boat in Halifax on Friday night and Saturday morning to find people who were possibly trapped in the flood.

Between May and June, Canadian wildfires forced thousands of residents to flee their homes and destroyed about 200 homes or structures, Nova Scotia officials estimated. As of Saturday, wildfires continue to burn across western Canada.

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