Police report that they received news that the cars were ablaze at around 2.30 am on Thursday morning. As well as seven police vehicles, several private vehicles and a car belonging to Deutsche Bahn (German Rail) were gutted by the flames.
Police say fire services were able to stop the fire spreading to a nearby storage facility and by 3.10 am the flames had been extinguished.
On Thursday police refused to rule out the possibility that there was a political motivation behind the crime.
In the former communist East German state of Saxony-Anhalt, where Magdeburg is the capital, there have been several attacks on police and army vehicles in recent years.
In 2012, 12 brand new police cars were set on fire in the state capital. Two days later, police cars parked at a police station in Halle were set on fire. Police never found the perpetrators.