The Canadian consulate in Hong Kong on Friday suspended all work travel to mainland China for its staff, days after British consulate employee was detained at the border while returning from neighbouring Shenzhen on a business trip.

“The consulate general of Canada in Hong Kong employs Canadian diplomats posted to Hong Kong as well as locally engaged staff. At present, locally engaged staff will not undertake official business travel outside of Hong Kong,” a spokesperson from the consulate told the South China Morning Post on Friday.

Simon Cheng, a Hong Kong national who works as a trade and investment officer for the British consulate was last heard from by his girlfriend on August 8 while going through border control at the West Kowloon high-speed railway terminus in Hong Kong.

His family filed a missing-person report with the Hong Kong police the next day.

China’s state-run Global Times newspaper reported on Thursday that Cheng had been detained for soliciting prostitutes, which is illegal on the mainland.

On Tuesday, the UK Foreign Office expressed “extreme concern” over reports that a Hong Kong consulate employee had been detained at the Chinese border.

“We are concerned by reports that a member of our team has been detained while returning to Hong Kong from Shenzhen,” an FCO spokesman said.

The British embassy in Beijing is providing support to the family, he added.

The semi-autonomous city has been shaken by historic demonstrations in the past eleven weeks when protesters demanded the withdrawal of a bill that would allow extraditions to the Chinese mainland and later the bill was suspended for now.