Police in Invercargill are investigating at least three suspicious fires in the city.
Senior Sergeant Bruce Terry said one of two teenagers was in police custody after a truck was set on fire in north Invercargill about 1am.
The other was treated for minor injuries at Southland Hospital.
A Police Dog unit tracked the teens for some distance before they were apprehended.
In another incident a car was found ablaze at Sandy Point just after 5.30am, he said.
