The incident is the second of its kind in consecutive nights and the latest in a string of similar fires in recent weeks.
Police are now investigating whether the burnings of 11 car in total in the Norwegian capital this week were started deliberately.
“We have activated a lot of resources. We are using both police helicopters above the city and police cars in the search. We have forensic investigation of the scenes and have sealed off the area,” operation leader Rune Ullsand of Oslo Police told NRK.
The car fires, which were in the Furuset and Tøyen neighbourhoods of Oslo, were all quickly extinguished by fire services.
The Tøyen fire involved six cars, spreading from one car to another, and there was a risk of flames spreading to nearby buildings in Oslo's old town prior to the fires being put out, according to the report.
Police asked residents to stay inside and keep windows closed while the fires were extinguished.
Reports of the fires were received by emergency services at 2:48 Wednesday morning and the flames were under control around 15 minutes later, according to NRK's report.
“In all cases such as these we take into account whether the fire was started deliberately. We are looking for suspects as well as cars that may have been involved. We are appealing for tips on cars that may have been seen driving away from the area between 2:30am and 2:50am,” Ullsand told the broadcaster.
Nobody has been detained in connection with the fires at the time of writing.
Photo: Terje Bendiksby/NTB scanpix
Earlier in the evening, police were also called out to the Micheletveien road in Furuset after receiving a report of two burning cars. This fire was also promptly put out.
“We are at the scene now and are investigating whether there may be a connection with other recent car burnings,” Ullsand said.
One witness reported seeing a white BMW driving at high speed from the area. Police are now trying to locate this vehicle.
The two cars that were burned in the fire have been taken in for technical examination.
Oslo has been plagued by similar car burnings in several locations in the city in recent weeks.
A number of burnings at the beginning of June are now being treated as arson by police.
Causes of further incidents on Tuesday this week, when there were three separate burnings, are still being assessed.
“The incidents are being investigated separately, but are being considered in the context related to their proximity and that they are all car burnings. We do not yet know whether they were deliberate, but cannot exclude this possibility,” section leader Rune Skjold of Oslo Police District told news agency NTB Tuesday.
All of the cars involved were empty when they caught fire.
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