Fire crews dealt with more than 40 deliberate fires every day last summer, figures show.
The Scottish Fire and Rescue Service (SFRS) warned of a “needless drain on resources” if the pattern repeats itself this summer.
Between June 1 and August 31 last year, 3,904 deliberate fires were recorded in Scotland – averaging 43 daily.
Of those, 694 involved a casualty or a rescue, or needed five or more fire services appliances to attend.
More than 3,200 incidents were classified as secondary fires, involving derelict buildings, unoccupied buildings, grassland or refuse.
Assistant chief officer David Lockhart, SFRS’s director of prevention, protection and preparedness, said: “Firefighters across Scotland were called to over 40 deliberate fires daily last summer, which is a needless drain on our resources.
“Most of these fires were secondary fires, involving derelict buildings, unoccupied buildings, grassland and refuse.
“In terms of derelict buildings in particular, these structures have the potential to cause great risk to members of the public, so please do not think of entering them for any reason.
“Deliberate fire-setting is not only reckless and dangerous but can divert SFRS resources away from genuine emergencies.”
The service works closely with Police Scotland and Fearless, a dedicated youth service of the charity Crimestoppers, to identify those responsible.
Lyndsay McDade, Fearless Scotland manager, said: “Deliberate fires are often started with no understanding of how quickly they can get out of hand, and cause not only significant damage but serious injury and risk to life.
“Fearless works closely with partner agencies, including SFRS, to reduce anti-social behaviour and deliberate fire-setting.
“If you know who is responsible for starting unsafe fires in your community, you can speak up to our charity 100% anonymously at Fearless.org. We can’t track your IP address or any contact details.”
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