Crews were first called at 9.21am after a large fire engulfed a warehouse in Old Parkbury Lane, Colney Street. Ten fire engines and an aerial ladder platform were sent to the scene. Deputy chief fire officer Mark Barber said: "We are currently responding to a fire at a large industrial unit in Ventura Park, Old Parkbury Lane, Colney Street, St Albans. "Please continue to follow our advice and avoid the area to allow emergency crews to work safely and effectively." Road closures are also in place in Colney Street and Old Parkbury Lane.