AN INVESTIGATION has been launched after a runaway wagon left a cement works, went over two level crossings and came to an abrupt stop just short of a railway line.

The Rail Accident Investigation Branch (RAIB) has launched a probe into the incident, which happened at 8.20am on March 9 when a tank wagon loaded with cement powder ran away from a siding located within the Hanson cement works in Clitheroe.

The wagon left the works and continued to run away on the descent towards Horrocksford Junction, where the line to the cement works connects to the main railway line from Blackburn to Hellifield.

As it ran away, the wagon broke through the gates at the exit from the cement works and ran over an open level crossing located on a road, causing two cars to stop.

A short distance later, the wagon passed over an open crossing on a second road.

A spokesman for the RAIB said neither level crossing had its manually activated warning equipment switched on before the wagon passed over.

THe spokesman said: "On reaching Horrocksford Junction, the wagon derailed on the trap points which worked as intended to prevent such unauthorised movements from reaching the main line. The derailed wagon stopped clear of the main line and no trains were nearby when the derailment occurred. The wagon ran away for a total distance of about 0.75 miles (1.2 km).

"Our investigation will seek to identify the sequence of events which led to the accident.

"It will also consider any factors relevant to the performance and design of the wagon’s braking system, how the risk of runaway wagons from within the cement works was controlled and any relevant underlying factors.

Our investigation is independent of any investigation by the railway industry or by the industry’s regulator, the Office of Rail and Road.

We will publish our findings, including any recommendations to improve safety, at the conclusion of our investigation."

Nobody was injured as a result of the incident.