Hua's wife, Deng Guilian, told CNN that she received a call Tuesday from police in Jiangxi telling her that her husband has been detained for conducting illegal surveillance and that she should expect to receive a formal notice in the mail soon.
According to Li Qiang, executive director of the group China Labour Watch, labour activist Hua Haifeng was arrested in Jiangxi province on suspicion of illegally using eavesdropping equipment. They were investigating Huajian Group factories in the southern Chinese cities of Ganzhou and Dongguan.
The Watch has been investigating working conditions at the factories of the world's most well-known companies for over 17 years.
"Wei Xuegang, who is an assistant to Huajian Group's president, said the firm" doesn't know about the situation", adding: "We haven't heard of this labor organization".
The company produces around 100,000 pairs of shoes for the Ivanka Trump brand every year, from a total output of eight million pairs.
And while President Trump made a pledge in his January inauguration speech to "buy American and hire American", US Customs bills of lading examined by AFP revealed that more than 50 tonnes of Ivanka Trump-branded shoes, bags and clothes were steaming towards American ports from China even as he spoke. The AP notes that they've also been unable to reach the families of the investigators. And with family's only breadwinner now in police detention, she said she's anxious about their financial situation. They were also forced to work for 12.5 hours per day, six days a week, receiving a monthly salary of roughly $363, or 1,500 Chinese yuan.More news: PM Narendra Modi meets German President Frank-Walter Steinmeier
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"I was scared when the police called me, I was shaking with a mix of fear and anger, " Deng told the Guardian.
Trump lambasted China over its trade practices during the USA presidential campaign, but he has established a friendly rapport with President Xi Jinping since they met at Trump's Mar-a-Lago resort in April. Marc Fisher, which produces shoes for Ivanka Trump and other brands, said it was looking into the allegations.
A labor activist who went undercover to investigate working conditions at a factory in China that makes shoes for Ivanka Trump has been detained by police, his wife said.
State police said Skeens, of Farmland, Indiana, and front-seat passenger Jordan were arguing when he punched her and grabbed the steering wheel.
Deng said the news came as a shock. The use of student workers in China is legal, but meant to be strictly regulated.
"If he is sentenced for this, I can't accept it, I can't accept it's justice", she said by phone from her home in the central province of Hubei.