Updated 5 March 2011 at 09:15
Police report Two 45-year-old men from Keighley and a 30-year-old man from Ilkley remain in custody as enquiries continue.
A cordon was placed around the building while fire fighters extinguished the blaze. As a safety precaution, roads surrounding the building were closed and trains were stopped from running on the line between Cononley and Steeton.
Substantial damage was caused to Speedy Hire, the fire also damaged a neighbouring business premises and other industrial units in the area sustained smoke damage. A passing train also sustained a small amount of damage.
No-one was injured and no residential properties were affected by the fire.
The fire is now under control and trains were allowed through the area again at around 6:30pm. Roads were reopened at around 7pm.
Police are treating the blaze as suspicious and have arrested three men from West Yorkshire on suspicion of arson, they are currently in police custody.
The scene of the fire remains under police control to allow police and fire investigators to carry out a forensic examination
Anyone with any information about the fire is asked to call police on 0845 60 60 247. Or you can give information anonymously to Crimestoppers on 0800 555 111.