Large gorse fires are burning in counties Donegal, Offaly and Sligo this afternoon.
The most serious fire in Co Donegal is in a forest at Bonnyglen, Loughfad in Glenties. Fire units from Glenties, Dungloe, Donegal Town and Killybegs are at the scene, as are three Coillte helicopters.
Local people are helping in efforts to contain the fire and other fire units from Ballyshannon and Glencolumbcille are on standby. There is a real danger the fire could spread to homes near the forest, according to Donegal's chief fire officer Bobby McMenamin.
Two Air Corps helicopters fitted with giant “Bambi” buckets capable of dropping 1,200 litres of water on the flames are at the scene of another serious fire at Muckish Mountain near Falcarragh. 32 army personnel are also in attendance.
Mr McMenamin warned landowners and the public to remain alert in the coming days.
“Conditions are still ideal for gorse fires,” he said. “We have windy conditions, very dry conditions out on the land and I would ask people to be very careful until the rain comes.”
Major fires in Dungloe, Ardara and Glenties have been contained but teams are still tackling several other smaller fires, including in Buncrana and Milford.
In Co Sligo, fire brigade units from Sligo, Ballymote, Tubbercurry and Enniscrone are attending a major fire at Dromore West. The Coillte helicopter is on the scene.
An Army spokesman said soldiers were also on standby to help tackle a number of fires on the Offaly/Meath border
A number of fires have spread onto Bord na Móna land between Ferbane and Edenderry in Co Offaly. Some 450 Bord na Móna staff are working "around the clock" to put out the fires and to prevent them spreading further into the boglands, according to Paul Riordan, head of peat operations at the company.
Mr Riordan appealed to landowners near the company's boglands not to burn gorse and heather, saying this was the main reason fires were starting and then getting out of control. He said the bogs were very dry after a spell of good weather and a lack of rain. He added there was evidence that some fires had been started deliberately.
"We hope to get these fires put out in the next 24 or 48 hours," he told RTÉ radio this morning.
David Thompson, coast and countryside manager with the National Trust in Northern Ireland, said it was "really worrying that people are deliberately setting fires to a wonderful natural resource like the Mourne Mountains".
He told RTÉ: "The fire service here say they've never known anything like this. They strongly suspect that the majority of these fires are started deliberately."
The fires are taking hold and spreading because the mountains are very dry after one of the warmest springs on record, he said.
The Northern Ireland Fire and Rescue Service said the holiday weekend had been the busiest in its history. At one stage, the service was getting a call every 45 seconds.
The Mournes; Ballycastle, Co Antrim; Gortin, Co Tyrone; and Rostrevor, Co Down, were badly affected. Chief Fire Officer Peter Craig said it had been "phenomenally busy".
Meanwhile, two boys, aged 10 and 15, were arrested yesterday on suspicion of setting fires in the Aghnagar road area of Sixmilecross, near Omagh, Co Tyrone.
The PSNI issued a warning today about the dangers of the fires, saying they were unpredictable, could change direction at any time and that visibility had been seriously reduced.
Met Éireann forescaster Pat Clarke said there would be no rain until tomorrow when persistent and heavy downpours are expected along the west coast, pushing across the country during the day.
Rain may not arrive in the east, including the Mournes, until as late as Wednesday night, he said. "That will be the pattern for the rest of the week: change and unsettled weather with showers or longer spells of rain moving in off the Atlantic from time to time," he said.
Mr Clarke said conditions would remain windy.
The Irish Chief Fire Officers Association (CFOA) described the outbreak of gorse, bog and forest fires throughout the country as "unprecedented".
Speaking ahead of the association's annual conference and technology exhibition in Limerick tomorrow, vice chairman Adrian Kelly said the geographical spread of incidents across the country had placed a huge strain on fire services in the affected counties.
“A combination of strong winds and the continuing dry conditions exacerbated the situation by causing fires to spread, particularly across Donegal. The arrival of rain in affected areas over the next 48 hours will provide a significant boost to emergency services in tackling the continuing threat of fires,” he said.
He said the association condemned people who had started fires deliberately. “Such reckless actions have placed the lives of both members of the local community and also firefighters at risk. These fires have also destroyed hundreds of acres of gorse land, forestry and bogs, with negative consequences for property, tourism and wildlife.”
Additional reporting: PA