Two men have been charged with conspiracy to commit arson after a series of fires over the past five months in Maidstone.
Kent Police said both men, aged 19 and 34, would appear before magistrates in the county town on Saturday.
The pair are also accused of making threats to commit criminal damage.
The charges relate to five fires at businesses in the area, including the offices of Faversham and Mid Kent MP Hugh Robertson in Lenham.
Each of the buildings was daubed with a yellow painted number in a circle to signify the order of the attacks.
A further 22-year-old man who was arrested for conspiracy to commit arson has been bailed pending further inquiries.