Samsung Electronics has been hit by fresh allegations of child workers at a Chinese supplier, a week after the South Korean group assured investors that there was no underage labor involved in making its products.
In the latest of a series of undercover reports on Samsung's and its suppliers' factories, the New York-based group China Labor Watch (CLW) on Thursday claimed to have found evidence of five child workers at Shinyang Electronic, a Samsung supplier in Dongguan, southern China.
The failure to ensure legal labor standards among Chinese suppliers has become a source of embarrassment to Samsung and other leading electronics companies.
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In its annual "sustainability report" last week, Samsung disclosed extensive illegal practices involving most of its more than 200 suppliers in China, with violations including lack of safety training and working hours over legal limits, which it had previously vowed to end by the end of 2012.
But Samsung said that extensive audits of all its suppliers, by an unnamed external agency, had found no evidence of child labor.
CLW condemned such assurances as "false advertisement meant to bolster its image as a responsible corporate citizen".
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Its report offered redacted photographs, employee passes and identity cards to support its claim to have found five 14- or 15-year old workers at Shinyang, all from the same nearby middle school.
CLW said that the workers had been hired using fake identity cards, with managers ignoring a verification system that Samsung said it had ordered all suppliers to use.
In a report compiled last month by an undercover investigator working at Shinyang, CLW claimed that the children often worked an 11-hour night shift, during which they assembled 700 smartphone parts an hour. It said they faced systematic discrimination, earning only Rmb7.5 ($1.20) an hour for weekend overtime work, less than half the pay for adult workers.
The group also accused Samsung of failing to respond appropriately to a previous CLW report of child labor in December 2012, which Samsung said it could not substantiate.
Calls to Shinyang on Thursday went unanswered. Samsung said: "We are urgently looking into the latest allegations and will take appropriate measures in accordance with our policies to prevent any cases of child labor in our suppliers."
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It stressed its "zero-tolerance policy on child labor", and said that a separate outside audit of the Shinyang plant last month by DNV GL, a South Korean agency, had found no child workers.
"We are moving as fast as possible to address the labor-related issues that have been identified from our own and third-party audits," Samsung said.
The problem of the underage labor problem in southern China was underscored last week by reports that another Dongguan manufacturer, Gang Gu Electronic, had sent home 192 "student workers" over allegations that many of them were under 16.
Last year Li Qiang, head of CLW, accused Samsung of being less committed to improving conditions at suppliers than its rival Apple, which has also been the subject of extensive criticism from CLW.
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While Samsung says that CLW's reports of children working at its suppliers are baseless and has never admitted child labour at any of its suppliers, Apple's latest audit of its suppliers reported 23 instances of child labour.
In contrast, Apple said 95 per cent of its suppliers adhere to a 60-hour working week, while Samsung said most of its suppliers break the legal limit on overtime.