Two Arriva buses were set alight by arsonists on Monday night, causing £230,000 worth of damage.
The incident happened at approximately 9.50pm at the Arriva bus depot in Dunstable Road, when petrol was thrown from a car park in the retail area off Chaul End Lane, into the depot setting fire to two buses.
Detective Constable Colin Knight, investigating, is keen to trace witnesses to the incident.
DC Knight said: “Luckily no one was injured during this incident but the fire could have spread had it not been contained quickly and put people in danger.
“I would urge anyone who saw anything suspicious in the area that night or anyone who noticed people standing in the car park close to Next, Currys and Vauxhalls, to contact the police and help this investigation.”
Anyone with information relating to this collision can contact DC Knight, in confidence, at Luton Police Station on 01582 394069, or Bedfordshire Police on 101, or text information to 07786 200011.
Alternatively you can contact the independent charity Crimestoppers, anonymously, on 0800 555 111.