Nearly half a million people are without power after Dorian slammed Atlantic Canada on Saturday, blasting the region with hurricane-force winds and wreaking havoc on the power grid.

More than 489,000 customers lost power after strong gusts uprooted century-old trees, toppled power lines and even knocked down a construction crane in downtown Halifax.

So far, no serious injuries or deaths have been reported.

Although the full extent of the damages is unclear, up to 700 military personnel are being deployed Sunday to help with the clean-up efforts, federal officials confirmed.

Dorian was initially expected to make landfall as a Category 1 hurricane, but the National Hurricane Centre in Miami later declared it a post-tropical storm.

Regardless, the storm still brought hurricane-force winds in excess of 150 km/h by the time it landed Saturday evening. Waves were expected to reach as high as 15 metres.

Howling winds also ripped the roof off an apartment complex in Halifax, throwing it onto cars in the parking lot below.

鈥淭here was just a really loud bang, and we looked out the window and the whole roof came down on the cars,鈥 a resident told 麻豆影视 after the building was evacuated.

is reporting outages affecting more than 378,000 customers, including more than 170,000 in the Halifax area. Karen Hutt, CEO of Nova Scotia Power, said a clean-up plan is already in the works.

鈥淢ore than 600 powerline technicians (are) ready to respond as soon as its safe,鈥 she said.

Nova Scotia is expected to get the worst of the storm, but other provinces in Atlantic Canada could see major damage and possible flooding. Bob Robichaud, the Canadian Hurricane Centre鈥檚 warning preparedness meteorologist, said flooding is likely.

鈥淲hen we get rainfall amounts that exceed 20 millimetres per hour -- which is very possible with this, almost likely, that overwhelms many systems -- and you tend to get flash flooding,鈥 he said.

FEDS CALL IN THE MILITARY

In New Brunswick, where more than 56,000 households and businesses lost power, some fishermen in Pointe-du-Chene decided to brave out the weather to keep an eye on their boats.

Many fishermen brought their boats in from the harbor in the days before the storm was set to hit, but others were unable to. With winds and rain lashing the docks and waves sending their boats jumping, fishermen tried their best to keep their boats safe.

鈥淚鈥檓 sure there鈥檚 going to be a lot of damage, the way it鈥檚 going now,鈥 Gilles Leger told 麻豆影视 at the docks. 鈥淚鈥檝e got the motors on in the boat, I鈥檓 trying.鈥

Another 50,000 households experienced blackouts in Prince Edward Island.

As the storm moved northeast toward Cape Breton through the night, residents were warned to stay indoors, not to drive anywhere and avoid the coast.

鈥淚t鈥檚 critical actually that folks take no chances. Hunker down and 鈥 keep yourself safe and your family safe,鈥 said Halifax Regional Police Insp. Don Moser.

Three evacuation shelters were opened in Halifax by the Canadian Red Cross to house anyone in need.

鈥淭hose that had to evacuate because of damage to their homes, they weren鈥檛 able to bring anything with them, so we鈥檙e giving them some comfort, some food, a place to lay down,鈥 said Ancel Langille, senior manager of emergency management for Canadian Red Cross Atlantic.

Provincial and municipal governments activated emergency plans, including cancelling some public services. Flights in and out of local airports have been cancelled. Ferry service and bridges were also closed in anticipation of the storm.

The Canadian Armed Forces will be deployed to Nova Scotia to help with recovery efforts, Public Safety Minister Ralph Goodale said in a statement. Prime Minister Justin Trudeau tweeted that "the safety of Canadians is our number one priority."

"The federal government will make resources available to deliver aid and assist with evacuations, where necessary. Citizens can rest assured that we are doing everything we can to help support the response efforts throughout Atlantic Canada,鈥 Goodale said.

STOCKPILING SUPPLIES

In Halifax, Erica Fleck, the city鈥檚 chief of emergency management, said officials contacted residents with loose objects on their properties as well as construction crews to prevent flying debris.

Halifax Water said emergency operations will be open 24 hours a day during the storm.

On Friday, the commander of Maritime Forces Atlantic said a group of NATO warships visiting Halifax were pulled out of the port.

"Just be ready for a storm that might knock out water service or wastewater, storm water service for up to 72 hours," James Campbell of Halifax Water told 麻豆影视 Atlantic.

"We don't anticipate there will be a loss of water service, but folks should always be prepared for that eventuality."

In the lead-up to the storm, many Maritimers were stockpiling supplies including propane, gasoline and groceries.

鈥淚t's more or less like panic buying,鈥 Fummi and Akin Odeniti told CTV Atlantic. 鈥淵ou know, you don't know what the hurricane is going to look like."

With files from The Canadian Press

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