Toronto police cordoned off a section of Front Street on Friday after large sheets of ice began falling from towering skyscrapers and even the CN Tower.

At least one vehicle, a taxicab, was damaged by the falling ice, but there were no reports of injuries.

Police closed off Front between John Street and University Avenue to pedestrians and vehicles as a precaution. Sections of Yonge, Spadina and Dundas were also affected.

Friday morning began with freezing rain lashing the city, prompting school boards throughout the area to cancel buses and classes.

But temperatures warmed later in the day, melting the ice and triggering the falling chunks.

Residents awoke Friday to see the damage caused by the freezing rain -- downed trees and hydro lines.

About 30,000 people were left without power as a result, Toronto Hydro said. By 6 p.m., between 10,000 and 20,000 customers were without hydro.

"We've got 225 wires down as of 8:30 a.m.," Toronto Hydro spokesperson Thelma Hatzis told CTV.ca. "That's in various pockets (of the city) and that's not including feeders that are out."

She added that Toronto Hydro had crews out all night in anticipation of the storm.

"We realize it's an inconvenience for (our customers) ... but our crews have been working really, really hard to get that power back on for those folks," Hatzis said.

Restoring power will take time, Toronto Hydro spokesperson Tanya Bruckmueller told CTV's Tim Weber.

"Unfortunately it looks like we're going to be moving into tomorrow, or even Sunday morning," she said.

Across Ontario, up to 80,000 people lost power. The largest outage was in the Bruce County, Walkerton and Clinton areas. Hydro One crews began repair attempts early in the morning, but bad road conditions hampered their efforts.

The March 1 storm dumped 10 centimetres of heavy snow before the freezing rain moved in.

By mid-morning Friday, the city's main concern was flooding.

Mayor David Miller said all litter pickup efforts, not home garbage collection, was diverted to clearing out catch basins in an effort to prevent flooding.

"I would urge Torontonians, in your own neighbourhoods or around your homes, to take the time to clear the catch basins so that water can get off the streets and flow away," he said.

The Toronto fire department was also been inundated with reports of downed power lines and tree branches strewn across roadways.

By 7 a.m., Pearson International Airport reported 100 flight cancellations as a result of the weather.

Commuters also faced delays on the TTC. The Scarborough RT was shut down Friday morning after a tree fell across the tracks near Lawrence Station. Shuttle buses were being used to take commuters between McCowan and Kennedy Stations.

Forecasters, meanwhile, called for another one or two centimetres of snow across the GTA on Friday afternoon.

On Thursday, police reported hundreds of collisions and vehicles in the ditch, while 100 flights had already been cancelled at Pearson by 6 p.m.

Motorists getting around the Toronto area were expected to take at least twice as long to get home. Some vehicles were also abandoned on the side of the road after having run out of gas during the current fuel shortage.

Police said icy roads and blowing snow could have played a factor in the deaths of two children in a collision near the southwestern Ontario town of Listowel. The victims were killed when they car they were in lost control and veered into the path of an oncoming tractor-trailer.

Their mother was taken to hospital with serious injuries.

The same weather system that rocked Ontario and headed towards eastern Canada on Friday also wreaked havoc in the United States, where it originated.

With reports from CTV's John Musselman and Paul Bliss