BARRIE, ONT. -- Eight people were injured, four seriously, when a tornado ripped through a Barrie, Ont., neighbourhood Thursday afternoon, leaving a trail of destruction in its wake.

During a press conference Thursday evening, Barrie Mayor Jeff Lehman said there were so far no fatalities.

"Everybody is accounted for, but it is early yet," he said.

Fire officials said crews were checking "under every bed and behind every door" to ensure no one was trapped in the rubble.

Officials said roughly 20 homes were damaged, and "about three or four" would have to be rebuilt.

Early Thursday afternoon, an Environment Canada tornado warning blasted over the airwaves and to cell phones as the skies darkened over the south end of the city and heavy rain fell.

Barrie resident Sheldon Murphy said they were in the kitchen when the warnings sounded.

"We saw stuff starting to fly around in the air, spinning. That's when we got everyone down in the basement. Then five minutes later, it started to clear up."

Environment Canada meteorologist Steven Flisfeder confirmed it was a tornado that touched down later in the day.

"At this time, based on images and videos, we can confirm that it was a tornado."

The storm lasted roughly 10 to 15 minutes and was followed by sirens as emergency crews headed to the Mapleview Drive and Prince William Way area.

Barrie police said thousands were without power as crews worked to repair hydro lines.

"It looks very symbolic, unfortunately, to a war zone in places," said Barrie police spokesperson Peter Leon. "The damage is catastrophic. It is significant, and it is major."

Barrie tornado

Lehman said the day's events brought him back to when a tornado hit the Allandale area in the 80s.

"I'm sure that people who lived through it in 1985, they can't believe, like I, that here we are dealing with another serious tornado in the city of Barrie.

But I can't tell you how incredible it is that nobody has been killed, and I hope that as all the secondary searches are completed, and the patients are treated at the hospital, that it continues to be the case. This certainly could have been a much more serious disaster," Lehman said.

Patients are being treated at Royal Victoria Regional Health Centre (RVH).

The Barrie hospital's president and CEO, Janice Skot, said staff and physicians were on standby "should extra resources be required."

Additionally, Simcoe County Paramedics provided triage at Saint Gabriel the Archangel Catholic School to anyone injured in the storm.

Police are urging anyone who doesn't live in the area to avoid it.

Premier Doug Ford posted to social media expressing his sympathy for those impacted by the storm.

"My thoughts are with everyone in Barrie and Innisfil affected by the severe weather today. A big thank you to our first responders that are currently on the ground helping the situation. Please stay safe everyone!"

Environment Canada said it would send a team to survey the storm damage in Barrie.

Barrie police have set up a central phone line for anyone in need of assistance, call 705-728-8442.