More than 200 deliberate gorse fires in 'tinderbox landscape'
Firefighters have tackled 221 gorse fires across Northern Ireland over the last five days and said 92% of them (204 fires) were started deliberately.
The Northern Ireland Fire and Rescue Service (NIFRS) has issued a warning after the spike, which coincided with a spell of dry, sunny weather.
Area Commander Maurice Rafferty said the conditions had "provided a tinderbox landscape" for gorse fires.
He added the arson attacks put lives and risk and put pressure on resources.
The fire stations which dealt with the most gorse fires over the past week were Downpatrick, County Down, which had 26 call-outs and Lurgan, County Armagh, which tackled 22 gorse fires.
During the same period last year, 1-5 May, NIFRS attended 19 gorse fires in total across Northern Ireland.
Mr Rafferty appealed to the public, and young people in particular, to "support their fire and rescue service by acting responsibly".
"Tackling gorse and wild land fires is extremely challenging for us. It means deploying firefighters and equipment to remote locations.
"This can be for prolonged periods of time with our crews working under hazardous and intense heat to bring the fires under control.
"These fires can easily spread and even a slight change in wind direction can pose a serious risk to life, property and the environment."