Arson is a crime. When someone deliberately sets fire to anything (such as a building or vehicle) they do not own and they want to cause damage, it is called arson. A person who commits arson is an arsonist. Arsonists usually use gasoline or kerosene to start a fire.
Arsonists use matches, Molotov cocktails and fire starters to start a fire. Arson is common in violent protests and retaliations against the government and other powers.