Detectives are investigating a blaze at a Dewsbury car lot.
Firefighters were called to the RS Motor Company on Huddersfield Road at Scout Hill late on Sunday night, where five cars had been set on fire.
Crews from Dewsbury Fire Station attended at 11pm and spent 45 minutes putting out the flames.
Nobody was on the premises at the time although the owner was informed and attended the scene.
Police have also been speaking to local residents.
A crew member from Dewsbury Fire Station said: “When we arrived, there were five cars on fire in the lot, where there were about 15 vehicles overall. An investigation is ongoing as to the cause, it’s thought to have been deliberately started.
“A few residents said they had seen another car parked up there.”