HONG KONG: Some Hong Kong-based staff with U.S. consultancy Mintz Group have left China, fearing future arrests as China expands it anti-espionage laws.

The Beijing office of Mintz Group was raided by Chinese police in March, who confiscated documents.

During the raid on the Mintz office, five mainland Chinese staffers were detained by police, including the head of Mintz's Beijing office.

Chinese authorities are continuing an investigation into Mintz, as well as U.S. management consultancy Bain and Co and mainland consultancy Capvision Partners.

Such tactics have sent a chill through companies that deal with China, with many unsure of the future of working in China.

Earlier, companies operating in Hong Kong had to learn how to navigate the new national security law Beijing imposed on the city in 2020.

It remains unknown whether those executives of western companies that have fled China will return when there is a clearer understanding of the new rules.

It is believed that Mintz came under police surveillance after the company undertook preparing a report on the use of forced labor in China's Xinjiang province.

Meanwhile, Reuters reports that employees of other consultancies have said that Chinese officials warned them not to report on the use of forced labor throughout the country.

Reuters further reported that the Mintz office in Hong Kong has been closed.

Following the police raiding Mintz's Beijing office in late March, the company closed its office, after releasing a statement that it was ready to work with the Chinese authorities to "resolve any misunderstanding that may have led to these events."

In recent years, the U.S. has warned its citizens working in Hong Kong of he greater risks of arrest, detention, expulsion or prosecution by Chinese authorities.

China's sensitivity about the reporting of its use of forced labor follows the U.S. publishing a list of companies it is sanctioning for using forced labour in Xinjiang. The US has also enacted laws that ensure that goods coming from China were not manufactured using forced labor.