A tree next was set alight next to an electrical junction box was in a residential area of Newry on Sunday night.
Police and the fire crews responded to the deliberate blaze in Clanrye Park.
A police spokesperson said: “The tree was next to residential properties and also near to an electrical junction box.
“Can parents please make sure you know where your children are and what they are doing.
“Taking a fire appliance off the ground to deal with this, means they are unavailable to respond to any other emergencies that may occur. This tree if not caught in time could have had serious consequences for local residents.”
SDLP Councillor Michael Savage said this “madness has to stop”.
He added: “The people of the area have suffered enough and eventually those involved could end up with a criminal conviction which can prevent travel and impact on future job opportunities.
“It’s time to bring this to an end before someone is badly hurt or ends up in serious trouble.”
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