The huge factory that employs some 79,000 workers in northern Taiyuan city erupted into violence late on Sunday and into the early hours of Monday morning after what the plant's owner, Foxconn Technology Group of Taiwan, described as a personal dispute that spun out of control.

Workers on Tuesday morning walked back through the gates of the factory, which was still ringed by police and showed clear signs of damage caused by the fighting, in which 40 people were injured, according to Foxconn and Chinese local media.

Some gates were still flat on the ground, having been bent over, and windows were smashed. A loud speaker on a loop recording called for people to maintain social order.

Foxconn, which assembles Apple's iPhones as well as making components for other global electronics firms, has faced accusations of poor conditions and mistreatment of workers at its plants in China, where it employs about 1 million people.

The company says it has been spending heavily in recent months to improve working conditions and to raise wages.

Foxconn spokesman Louis Woo said on Tuesday that the one-day closure would not disrupt supplies from the factory.

"We have 79,000 people working in the Taiyuan campus, and we always have spare inventory," Woo said.

Foxconn does not confirm which of its plants supply Apple, but an employee told Reuters that the Taiyuan plant was among those that assembled and made parts for Apple's iPhone 5.

Foxconn said in a statement the incident had escalated from a row between several employees at around 11 p.m. on Sunday in the privately managed workers' dormitory, and was brought under control by police at around 3 a.m.

Comments posted online, however, suggested security guards may have been to blame.

Foxconn is the trading name of Hon Hai Precision Industry Co, the world's largest contract maker of electronics.

(Reporting by Michael Martina in TAIYUAN and Clare Jim in TAIPEI; Editing by Mark Bendeich and Ken Wills)

• A Permanent Economic Emergency