Police are appealing for witnesses after an arson attack caused £1m worth of damage to the fleet of haulier AET Transport Services.
No one was injured in the blaze at the firm's premises, near Wareham, Dorset, but six lorries and five trailers were destroyed.
The fire was reported by a woman who heard several explosions around 7.30pm on Saturday night.
Detectives believe that a trailer and fork-lift truck - normally towed by an articulated lorry - were stolen during the fire and are appealing to the public for help in finding them.
According to reports in Bournemouth's Daily Echo, managing director Andrew Trotter has vowed to keep the firm running using a rented fleet in the short term.
AET Transport Services specialises in transporting machinery used in the manufacturing sector. It has a fleet of 18 vehicles, hydraulic jacking equipment and three Versa-lift fork-lift trucks.
Witnesses and anyone with information should call Dorset Police in confidence on 01202 222 222 or the free and anonymous Crimestoppers line on 0800 555 111 where mobile phone tariffs may apply.