Three people were arrested on suspicion of arson tonight after an explosion at an industrial unit. The men, who were from West Yorkshire, were in custody this evening. Fire crews from stations in West and North Yorkshire were scrambled to the scene of the blast in Cross Hills, near Keighley, at 4pm today. Cylinders containing propane, acetylene and Hilti gun cartridges were believed to have been at the premises. Flames were described as having ‘shot’ from the building, which belongs to plant and tool hire firm Speedy Hire, at the Enterprise Centre, off Skipton Road. As a safety precaution, roads were closed and trains were stopped from the line between Cononley and Steeton. Substantial damage was caused to Speedy Hire. The fire also damaged a neighbouring business and other units in the area suffered smoke damage. Minor damage was caused to a passing train. Fire crews from Skipton initially attended reports of the fire and quickly requested the attendance of further appliances. A spokesman for Keighley fire station, which sent crews to the incident, said cylinders had exploded. But it was unclear last night what was contained in the cylinder or cylinders which had exploded. The unit was evacuated and no-one was believed to have been injured in the blast. Crews were continuing to damp down at the scene this evening. An investigation into the cause of the blaze and explosion was under way. Rush-hour traffic had faced major delays after the incident with one witness describing the roads as “chock-a-block” from the Cross Hills roundabout going towards Steeton. Anyone with any information is asked to call police on (0845) 6060247 or Crimestoppers, anonymously, on (0800) 555111.