© AP Photo
Father Ma Zishan and sister Ma Liqun mourn the death of Ma Xiangqian outside a Foxconn factory in Longhua. Mr Xiangqian killed himself in January.
Foxconn, the Chinese maker of Apple's iPhone, is investigating the death of a packaging plant worker, following a string of 13 staff suicides at its factories earlier this year.

The 22-year old woman died on Wednesday after falling from a dormitory building at its Kunshan plant in eastern Jiangsu province, the world's largest contract electronics manufacturer said on Friday.

Thirteen Chinese employees have committed suicide this year at Foxconn plants and an affiliate by jumping from buildings, including 10 in the southern city of Shenzhen.

It was unclear whether the latest death was a suicide. The company said it was working with local authorities to investigate.

The suicides at Foxconn - which generates revenues of $40bn annually making everything from iPads to desktop computers and televisions - have put the spotlight on working conditions for millions of factory workers in China, the "workshop of the world".

Protestors in May laid traditional Chinese funeral offerings at Foxconn's headquarters in Hong Kong. Employment rights campaigners have also criticized the "military-style" regime at Foxconn's Longhua plant in Shenzhen in particular, where 300,000 people work.

Company founder Terry Gou was earlier this year cleared by Chinese authorities of any wrongdoing in the period leading up to the suicides. He has said none of the suicides was directly work-related.

In June, Foxconn instituted two dramatic pay increases for its workers, designed, it said, attract better-qualified workers at a time when there are labor shortages across China's manufacturing belts.

Following the latest rise, which will take full effect from October 1, the basic salary for production-line workers at Foxconn's will have risen from 900 renminbi (£91.30) per month two weeks ago to 2,000 renminbi (£203).

The company employs more than 800,000 workers in China.