Three cars were deliberately set on fire at an Audi dealership in Hamilton, near Glasgow, on Sunday.
The fires were started in the evening of November 29 and officers were called to the site of Hamilton Approved Audi at around 10.25pm.
Scotland Fire and Rescue Service then extinguished the fire and there were no injuries.
Police in Lanarkshire are now appealing for information from anyone who might have been in the area or witnessed the fire.
They have also requested particular help from those who may have been driving near the dealership around the time of the fire and use a dashcam.
Detective constable Andrew Sinclair, of Lanarkshire CID, said: ‘The surrounding area was busy around the time of the incident so I would ask anyone with dashcam footage that could assist us with our investigation contact police.
‘I would also ask anyone who noticed anyone acting suspicious in the area to get in touch.
‘Anyone with information should contact police via 101, quoting incident number 3410 of 29 November. Alternatively, information can be passed anonymously through Crimestoppers on 0800 555 111.’