Car fires: Wrexham has half north Wales total so far in 2012
Half of all deliberate car fires in north Wales this year have been in Wrexham county, according to firefighters.
Of the 42 deliberate car fires across the region so far in 2012, 21 were in Wrexham, including eight this week.
Some have been started on driveways, increasing the risk of them spreading to housing.
North Wales Fire and Rescue Service and North Wales Police are appealing to Wrexham residents to be on their guard.
This week, fires in Holywell and Bangor were tackled by fire crews, but the eight incidents in Wrexham are a concern for the emergency services.
"The issue of deliberate car fires in Wrexham has been ongoing for some time, numbers fluctuate and spike every now and again," said the fire service arson reduction manager, Kevin Jones.
"Very often the cars are parked near to residential properties and there is a danger that the fires could spread causing damage to the house and serious injury to the occupants."
Since 1 April 2011, there have been 177 deliberate car fires across north Wales. Of these, 91 were in Wrexham, with 33 in Flintshire and 12 in Conwy.
Mr Jones warned that when fire crews are tackling a deliberate car fire, call-outs to life threatening incidents could be delayed.
He added: "This type of activity is a serious drain on fire and rescue resources - when crews are called to attend life threatening incidents such as house fires and road traffic collisions, appliances are not diverted from a deliberate fire, the next available fire appliance is mobilised. This may involve a time delay which could prove fatal."
Anyone with information is asked to call 101 or contacting Crimestoppers on 0800 555 111.