Union official Sean Morgan said workers had been told at a mass meeting early this afternoon that a faulty part sent from the US had prompted the shutdown of manufacturing.

The closure is indefinitie with the union working with management to determine how the problem can be solved.

The part is integral to the gearbox making process.

The stand down applies from the end of this afternoon's shift at 3.30pm.

Mr Morgan was shocked to learn of the problem after arriving to discuss redundancies at the factory.