A major fire which has already destroyed more than 200 acres of gorse in the scenic Mountains of Mourne in Co Down was being allowed to burn tonight in the hope approaching rain may put it out.
A fire service spokesman said it was too dangerous to send firefighters into the mountainous area around the Silent Valley.
"There is no life threatened and no property risk, so we have to balance that with risk to firefighters," he said.
He said the terrain was steep, the wind was changing direction and all that was at risk from the fire was vegetation.
He said the service obviously wanted the fire out and officers were at the scene drawing up plans. However, they were monitoring the situation before acting further and hoping for rain.
The unusually long dry spell in recent weeks has left the countryside tinderbox dry, and there have been a number of major fires.
Rain is forecast and the fire service is hoping that will dampen down the fires.
Meanwhile a blaze at the Ballykinlar army base a few miles from the Mountains of Mourne and close to Dundrum Bay was brought under control today.
The fire started yesterday morning close to the firing range and was not stopped from spreading until more than 400 acres of gorse had been burned. Hundreds of troops from the base joined firefighters with 13 appliances in tackling the blaze.