Unknown assailants set the car of a Turkish consulate employee ablaze early on Monday in the northern Greek city of Thessaloniki, a police official said. Authorities were investigating the incident which took place around 3:30 am, Reuters reported. "There was extended damage," said the official who declined to be named. There were no injuries. Arson attacks are not uncommon in the country which has a history of political violence. Athens and Ankara, NATO allies, are at odds over various decades-old issues ranging from mineral rights in the Aegean Sea to ethnically split Cyprus. A recent deal between Turkey and Libya over maritime boundaries has angered Greece, which sees the move as infringing its own sovereign rights.