Five employees at a North York seniors' home have been transported to hospital after falling ill with suspected carbon monoxide poisoning.

The employees reported feeling sick late Tuesday morning which prompted the evacuation of the residence at 1800 O'Connor Dr. near Victoria Park Avenue.

According to Toronto EMS, one of the victims is suffering serious injuries while the other four are being treated for minor injuries.

High carbon monoxide levels have been detected inside the building, EMS officials told CP24.

Meanwhile, the Toronto Transit Commission has been asked to provide six buses to shelter evacuees at the seniors' home.

Fire crews are on scene ventilating each section of the building. Toronto Fire said they've yet to identify the source of the carbon monoxide leak.

O'Connor Drive is closed between Victoria Park Avenue and Sunrise Avenue as emergency crews deal with the situation. It's not yet clear how long the closure will be in effect.