The warning came as arson suspects included at least one joyrider on a quad bike who was believed to have set a hill alight.
On the third day of gorse and forest blazes, extra soldiers were sent from Galway and Athlone to join troops from Finner Camp in Bundoran, Co Donegal, adding up to 100 army personnel to assist more than 100 firemen battling the blazes in Donegal.
Three Air Corps helicopters — two fitted with giant “Bambi” buckets to pour thousands of litres of water on the flames — and other choppers sent up by Coillte to protect forests were in the air over several areas of Co Donegal.
Farmers with slurry tanks and hand-held backpack sprayers spread water around homes and animal sheds in a bid to protect them from gorse fires across Donegal, Leitrim and Sligo.
Although people escaped injury, several homes were evacuated in the adjoining Knather and Coolcholly areas of Ballyshannon where one house was seriously damaged.
Town councillor John Meehan, who left with his family to spend Sunday night with relatives, said: “A number of families with young children felt they had to stay away overnight to avoid smoke inhalation.”
In Newtownmanor, near Manorhamilton, Co Leitrim, an evacuated new house was gutted when the wind swept flames to an outside oil tank. Gorse fires also swept west Co Sligo.
In Donegal, helicopters hired by Coillte, were spreading water in addition to Air Corps helicopters.
Coillte south Donegal forestry manager Kieran Moloney said: “We are using helicopters to try and contain the fires to the forests and hills. If the weather keeps like this we can expect further outbreaks in coming days.”
Four homes outside Ardara were threatened as fire raged towards them.
Town traders’ chairman Stephen McCahill, who lives in one of the houses, said: “The local community saved my home and three of my neighbours’ houses.
“I could see in the distance there was a blur of half a mile of fire coming towards the house.
“The fire had reached the road within 10 minutes and our four houses were right in line with the fire. There were flames 30ft high.
“Farmers came from everywhere with their slurry tanks and water tanks as the fire services were stretched elsewhere,” he said.
The worst blazes continued in west Donegal,though firemen were also battling flames in the Inishowen and Fanad peninsulas. Roads linking Dungloe amd Lettermacaward and Dungloe and Doochary were closed and warnings were issued to the public to remain away from those areas.
Danny Bonner in Cloughwilly, west Donegal, said farmers were left defenceless from Saturday evening until Sunday afternoon when troops joined firemen.
“There was no plan on the part of Government to defend the environment and small farmers are losing their livelihood,” he said.
Donegal County fire chief Bobby McMenamin said he believed some blazes were started deliberately.