"There was an outbreak of acute diarrhoeal disease reported among the Foxconn employees," the statement from the Thiruvallur district administration said.

It said 256 workers were treated as out-patients and 159 were hospitalised, of whom 155 have already been discharged.

Foxconn did not immediately respond to a request for comment.

It was not clear whether the incident would disrupt production at the plant in Sriperumbudur, which is on the outskirts of the southern city of Chennai.

Most of the Taiwanese manufacturer's workers in India are women.

(Reporting by Sankalp Phartiyal and Sudarshan Varadhan; Editing by Michael Perry and Helen Popper)