Two persons, who used to set parked vehicles on fire to teach lesson to cops and locals, have been arrested along with country made pistol and ammunition, police said on Friday.

Police said three consecutive incidents of arson on parked vehicles in the colonies under Kanjhawala police station in Rohini area were reported during night hours on September 23-24, in which more than dozen cars and two wheelers were set on fire by unknown persons.

Three separate cases were lodged and investigation was taken up, police said, adding that these were blind cases as no one knew the identity of the criminals.