The synthetic textile industry is reeling from a month-long strike that it is estimated has cost the affected companies more than 200bn won ($154m).

Policemen were called in to break up protesting workers at Hyosung's Ulsan plant at the beginning of June and the Korean Confederation of Trade Unions demanded an investigation into the use of guards to break up the strike.

The Ulsan plant is operating at 80 per cent of its capacity with losses amounting to 75.9bn won ($58.5m).

Other companies hit by the strike are Kohap and Taekwang Industrial, whose policy of pushing early retirement plans for 251 workers at its synthetic textile factory led to the workers' protest.