As work crews got the number of Toronto residents without electricity down to under 200,000 late Monday, police east of the city reported that two people had died of carbon monoxide poisoning from a gas generator being used to heat their home.

Durham Regional Police said a 52-year-old man and a 72-year-old woman died after fumes from a gas generator running got into the home in Newcastle, a community about 80 km east of Toronto. Thousands of residents there were left without power after Sunday’s ice storm.

The news came as work crews in Toronto made slow progress restoring power to the hundreds of thousands of customers left in the dark.

Mayor Rob Ford announced Monday afternoon that the number of Toronto residents without electricity is down to 195,000, with Toronto Hydro updating that number late Monday to 192,000.

It could be days before electricity is fully restored.

“We’re going to stay here every day, including Christmas Day, until every light is on in the city,” Ford told reporters shortly after 4 p.m.

Earlier, four more community centres were added to the list of warming centres where residents without power can go to warm up and have a meal. The new centres are: Lawrence Heights, Armour Heights, East York Civic Centre and Pleasantview Community Centre.

The mayor also announced that 11 Toronto police divisions have now been opened to the public.

Ford said warming centres were expected to get busier as temperatures were expected to drop Monday evening. Environment Canada forecasted a low of -11 C Monday night with northwest winds gusting to 20 km/h. Tuesday’s forecast calls for a high of -10 C, with Tuesday night hitting a low of -14 C.

Earlier at a morning news conference, Toronto Hydro CEO Anthony Haines stressed that, while Toronto Hydro hopes to have power restored by Christmas Day, it can make "no firm estimates" and there may be some pockets of the city where it will take longer.

"At this point we simply don't know the work that we have ahead of us," he said, adding that making a promise at this point would be "irresponsible."

Haines said crews have not been to every affected neighbourhood as they focus on restoring hydro along the city’s “main corridors.”

Outside support for hydro crews

Ford announced at the afternoon press conference that 100 hydro trucks from other provinces as well as from the U.S. were on their way to help. Haines said that some are expected to begin arriving Tuesday with others expected on Christmas Day.

Haines told reporters at Queen’s Park early Monday evening that he expects to send many of these crews to the areas his trucks have yet to visit.

“We’re not stopping until all the lights are on,” he said.

Haines said that although the imminent arrival of outside help “makes me feel much more at ease,” he is still advising residents to “plan for the worst” regarding a timeline for all power to be restored.

Hydro crews have been working around the clock since the ice storm brought down trees and hydro wires across the city over the weekend.

Haines said Monday morning that power had been restored to two of the city's water plants, as well as Toronto East General Hospital. The work took longer at Sunnybrook Hospital, which announced at 5:30 p.m. local time that power had been restored.

After power has been restored to critical infrastructure, hydro crews will tackle the major wires that serve a lot of customers, Haines said. Then, crews will proceed to smaller areas, where individual houses may be affected.

Residents can check the status of Toronto Hydro's work by checking its map of the power outages.

Reports of any downed wires can be made by calling 416-542-8000.

City not under a state of emergency

Ford reiterated Monday afternoon that the city is not declaring a state of emergency, as progress is being made to restore power in the affected areas.

“If conditions got worse last night, I think that could have been a possibility,” he told reporters.

Haines said Toronto Hydro’s operations are not affected by whether the city declares a state of emergency.

“Toronto Hydro has been, although under great pressure to get the lights back on, our operations have been operating under our (emergency) protocol since Saturday night,” Haines said.

Deputy Mayor Norm Kelly told CTV's Canada AM that the city is already in talks with the province on a "pragmatic" way it could help, if required.

"So the declaration of an emergency may in many respects be a technicality," he said.

If a state of emergency is declared, Kelly said authority to manage it would fall to him and not Ford. Ford was stripped of most of his executive powers, including his authority over a declared state of emergency, after a vote by city council in November.

TTC service resuming, slowly

Meanwhile, TTC service was gradually returning to normal Monday.

Streetcar and bus service across the city has resumed, TTC CEO Andy Byford said Monday afternoon. However, a number of bus routes are on diversion due to debris on the roadways.

The Scarborough RT resumed service just after 1 p.m., and at approximately 2:30 p.m. the TTC announced in a tweet that service had resumed on its Bloor-Danforth subway line, where shuttle buses had been running between Kennedy and Woodbine stations. The TTC has also announced that full service had resumed on the Yonge-University line.

The Sheppard subway remains out of service. Byford said Monday afternoon that he doesn’t not have a timeline for when service will be restored. However, shuttle buses are operating along the route and additional TTC staff are at Sheppard station to direct customers.

GO Transit running on 'adjusted service' schedule

Go Transit is operating on an 'adjusted service' schedule today, with all lines operating with reduced service. Commuters can keep up to date on GO Transit service by checking its website.

Thousands without power outside Toronto

Just outside the city, in Vaughan, Richmond Hill, Thornhill, Markham and Aurora, PowerStream tweeted it expected to have the majority of customers back up by the end of Monday.

HydroOne tweeted early Monday morning that it was working to reconnect roughly 120,000 customers who were still without power across southern Ontario. By Monday evening that number had been reduced to 52,000.

Premier Kathleen Wynne told reporters Monday evening that the province’s emergency management office is working with all affected municipalities to address their needs, and field officers have been deployed to assess damage.