Staff at a car dealership in Milton Keynes had a narrow escape, after 20 cars fell through the roof and into a workshop.
Milton Keynes Audi, which is operated by Jardine Motors Group, was evacuated after a 100ft by 65ft section of the ceiling collapsed on Monday afternoon, under the weight of cars stored on an upper level.
No one was injured in the freak accident, though a number of high-end models suffered extensive damage. Firefighters were reported to have been propping up the remainder of the ceiling to prevent a further collapse.
A Buckinghamshire Fire and Rescue Service spokesman said: "Firefighters assisted with scene safety following a partial roof collapse at Milton Keynes Audi.
"One appliance and crew from Broughton attended, along with two officers. About 20 vehicles fell through to the workshop. The building was safely evacuated before it happened. No one has been injured.
"Building control and construction engineers also attended. The services were isolated and the building was left with the occupier."
Jardine Motors Group is investigating the cause of the collapse. In a statement on its website, the company said: "Part of the roof of Milton Keynes Audi, covering the workshop area, collapsed at midday on 1st June 2015 and the building has been evacuated.
"We have enacted our Business Continuity Plan, including the support of the Audi dealership team, to ensure that we can provide a suitable service level to all customers as soon as possible. All customers directly affected by this incident will be contacted in person."