Several employees of a Foxconn India unit, which makes iPhones for Apple Inc, were hospitalised on Saturday after a bout of food poisoning, a source familiar with the matter said.

The food poisoning occurred earlier this week at Foxconn’s dormitories, where a majority of its staff lives, said a second source. A bulk of the Taiwanese manufacturer’s workforce is women.

It was not immediately clear how many workers are seriously ill and whether the incident would disrupt production at the plant in Sriperumbudur, which is on the outskirts of the southern city of Chennai. Foxconn did not immediately respond to a request for comment.