Heavy smoke from wildfires in northern Saskatchewan forced hundreds more people from their communities and it’s unclear when they will be able to return home.

Officials said about 20 of the more than 100 fires burning in the province on Monday had been extinguished by Tuesday, but persistent dry conditions contributed to about 10 new fires.

Although more firefighters arrived from as far away as Newfoundland Tuesday, water bombers were grounded by smoke so thick that pilots couldn’t see far enough to fly.

Some major roads and parts of Highway 2 were shut down Tuesday.

An estimated 4,000 people have left their homes since the fires started.

Reta Nawakayas was forced to leave Red Earth First Nation and travel five hours south by road to a shelter at the University of Regina.

“I had a hard time when I got here last night,” she said. “I got sick because of the smoke when we were travelling. They had to put oxygen on me.”

Albert McCallum of Île-à-la-Crosse travelled even further, about 800 kilometres.

”It happened all of a sudden yesterday,” he said. “We got up in the morning and it was just thick smoke.”

The biggest fire, near Prince Albert National Park, has burned the equivalent of 9,000 football fields. Fires near Île-à-la-Crosse and La Ronge are described as out of control.

Premier Brad Wall said the province has already used up its firefighting budget for the year, “but we’re not going to worry about that right now.”

Environment Canada, meanwhile, issued a warning to people across the province to reduce their outdoor activities due to poor air quality.

“The smoke is expected to persist over the next couple of days as winds will remain from the northwest and little to no precipitation is expected to flush out the smoke and haze.”

With reports from CTV Saskatoon and CTV Regina