The New York-based group China Labor Watch said the factory forced workers to sign fake pay stubs with inflated salary numbers, among other allegations.
The Huajian Group, which owns the factory, said allegations against it are "completely not true to the facts, taken out of context, exaggerated." It also said it stopped producing Ivanka Trump shoes months ago.
Meanwhile, Chinese authorities have released on bail three activists who were detained after investigating labor conditions at the factory that produced shoes for Trump and other brands.
The three activists walked out of a police station in Ganzhou, a city in southeastern Jiangxi province, on Wednesday, the final day of their legally mandated 30-day detention period limit.
The activists were working with China Labor Watch to investigate factories in the southern Chinese cities of Ganzhou and Dongguan.
China Labor Watch said the three men were released on bail pending trial.
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