One man has been arrested and two others are missing in southern China after conducting an investigation into a Chinese factory making Ivanka Trump-branded shoes, China Labor Watch, a New York-based advocacy group, said on Wednesday.

"We appeal to President Trump, Ivanka Trump herself, and to her related brand company to advocate and press for the release our activists," China Labor Watch said in an email to Reuters.

Labor activist Hua Haifeng was arrested in the southern province of Jiangxi on suspicion of illegally using eavesdropping equipment, according to Li Qiang, executive director of China Labor Watch.

The three men had been investigating a factory which makes shoes for the Ivanka Trump brand and other Western brands, he said in an email.