Foxconn, the Taiwanese manufacturing company whose clients include Apple, Dell and HP, has reportedly shut down production at one of its Chinese factories after riot broke out last night.

According to the Xinhua news agency, a fight broke out in a dormitory at the company's Taiyuan facility at 11pm last night. Forty people were injured in the ensuing brawl, which attracted as many as 10,000 spectators.

Reuters reported that a Foxconn spokesperson said the "plant is closed today for investigation". However, Xinhua said that a government official denied this.

Foxconn, which has been heavily criticised for its treatment of workers, described the riot as a "personal dispute". "The cause of this dispute is under investigation by local authorities and we are working closely with them in this process, but it appears not to have been work-related," the company said in a statement.

Reuters cites "an employee" as saying that the plant in question is involved in the manufacturer of Apple's new iPhone 5 smartphone.

Whatever the effect the disruption has on production, the story is likely to refocus public attention on the human cost of smartphone boom.