A tornado damaged cars in Gatineau, Que., and houses in a community west of Ottawa on Friday afternoon as much of southern Ontario saw severe thunderstorms and high wind gusts, Environment Canada said.

Ottawa mayor Jim Watson says approximately 60 buildings have been destroyed in Dunrobin, a suburb of Ottawa.

“During my time I haven’t seen anything of this magnitude that’s affected so many buildings,” Watson tells CityNews. “Our paramedics had a drone over the site, it looked like a war zone, quite frankly. We’re just very, very grateful that no one was killed.”

The Ottawa Hospital said in a tweet late Friday night that it was treating six people with storm related injuries, including two who were in critical condition, one with serious injuries, and the others listed as either stable or in fair condition.

Peter Kimbell, a meteorologist with the national weather agency, said the tornado overturned cars on Highway 50 in Gatineau and caused extensive damage to houses in Dunrobin.

Fire trucks lined streets in Gatineau, where debris and downed trees covered roads. Massive billboards were also overturned near the Sabourin arena.

The city issued a statement Friday announcing the opening of a mobile command post and an emergency measures centre. Municipal authorities also carried out evacuations in collaboration with the Red Cross and the campus of Cegep de l’Outaouais was converted into a disaster centre.

Prime Minister Justin Trudeau urged residents of both cities to “stay safe, follow the instructions of first responders and check in with people who might need extra help.”

“We’re monitoring the situation and thinking of everyone affected,” he said on Twitter.

Kimbell said tornado warnings were still in effect in the Ontario communities of Prescott and Russell. A line of thunderstorms running from west of Ottawa and into Gatineau were expected to continue for several hours, he added.

“The worst, I think, is over, but there is the potential for more,” Kimbell said of the Ottawa region.

Ottawa resident Glenn Johnson said he and his partner were in their kitchen just after 5:30 p.m. when the storm blew out their windows.

“We were trying to get down in the basement … and glass started flying,” said Johnson, who lives in Nepean. “My partner got her foot cut and I got hit with flying glass as we were trying to get the dogs and cat and everything down in the basement.”

He said the roof of his neighbour’s house was torn off and the second storey of another house was gone by the time the intense system passed.

“You can’t even get down the street because there are so many giant trees that had been taken down,” Johnson said. “My backyard just looks like a junk yard right now.”

He said he has gone door to door to check on neighbours. No major injuries have been reported.

“There had been kids in the park right behind our place up until about 15 minutes before this happened and there was a big tree that went down in the park where the kids’ playground is,” Johnson said. “It could have been much, much worse.”

Meanwhile, Ottawa Hydro said there were more than 147,000 power outages in the city because of the storm.

We can confirm there are outages to over 85,000 customers across #Ottawa as a result of the storm (including damage from winds, lightning & tornado activity). There is significant damage to the grid and all crews are out assessing damage and will establish a priority restoration. — Hydro Ottawa (@hydroottawa) September 21, 2018

The Greater Toronto Area saw thunderstorms and wind gusts of up to 80 kilometres per hour, also leaving thousands without power.

Hydro Toronto said on Twitter that more than 8,600 customers were without power and restoration efforts were expected to last into Saturday.

We have all available crews out in the field. They're working in dangerous conditions and at times, are not able to start repairs until the wind weakens.

No individual ETORs available at this time. — Toronto Hydro (@TorontoHydro) September 21, 2018

Alectra Utilities, which covers most of the GTA, said more than 6,000 residents were without power.