The police are investigating additional leakage of hydrofluoric acid at the Hwasong plant of Samsung Electronics in Gyeonggi Province following a similar incident that injured three workers April 3.

The local police and a forensic team is looking into the cause of the leakage and who are responsible.

They have called in employees of not only Samsung Electronics but those of contractors who installed the pipelines that supply the hydrofluoric acid into the plant.

Samsung officials said the reporting of the leakage was delayed by three hours because they were surveying ways determining seriousness of the situation.

The police, while questioning those who could be involved, are checking CCTV (closed circuit television) footages to check how the leakage occurred.