The Foreign Office has updated its travel advice for people travelling to Hong Kong amid continuing protests.

British travellers heading there have been warned that their electronic devices could be checked at the border between the city and mainland China.

The updated advice comes as supporters of Hong Kong's pro-democracy movement created human chains on both sides of the city's harbour, inspired by a historic protest 30 years ago in the Baltic states against Soviet control.

The online advice reads: "In light of ongoing protests and demonstrations in Hong Kong, there are reports of greater scrutiny from mainland authorities at border crossings between the mainland and Hong Kong.

"This includes reports that travellers' electronic devices have been checked at border crossings.


"You should be aware that the thresholds for detention and prosecution in China differ from those in Hong Kong."

Pro-democracy protesters line the streets and harbour in an ongoing campaign.

The updated advice comes as supporters of Hong Kong's pro-democracy movement created human chains on both sides of the city's harbour, inspired by a historic protest 30 years ago in the Baltic states against Soviet control.

Tom Cheshire, Sky's Asia correspondent, experienced lengthy checks after arriving at Beijing Airport on Thursday.

He said: "Just been detained alone for two hours at Beijing Airport arriving from Hong Kong.

"No reason was given apart from 'random check'. A call to the British embassy was refused, belongings searched, photos looked at, questions about Hong Kong."

The human chain demonstration came after British consulate worker Simon Cheng Man-kit went missing two weeks ago after going on a business trip to the mainland city of Shenzhen.

Chinese officials said Mr Cheng had been placed in administrative detention for 15 days for violating public order regulations, but gave no further details.

Ma Hui, a minister in the Chinese embassy, told Sky News: "This is a public security issue. He violated public security law according to the law and will be dealt with by the law."

He said he did not know specific details about the arrest, including reports that Mr Cheng had been arrested for visiting a brothel when he was in fact on a train.

Mr Cheng has been working for the British consulate since December 2017 as an international trade and investment officer for the Scottish government.

He and other local staff at consulates and embassies support diplomats, but do not have diplomatic passports themselves.

Protests in Hong Kong began 11 weeks ago with calls to scrap a now-suspended extradition bill.

Image: Simon Cheng Man-kit reportedly failed to return to Hong Hong from Shenzhen in China 10 days ago

They have since widened to include demands for full democracy and an independent inquiry into alleged police brutality during the demonstrations.

Travellers flying to Hong Kong have also been told to expect disruption and allow extra time for travel over the weekend.

The Foreign Office said: "A large protest action is also planned for August 24 (Saturday) targeting the transportation system to and from Hong Kong International Airport, and in the Kowloon East Kwun Tong area.

"Passengers are advised to allow extra time to travel to the airport."

Previous advice for travellers read: "You should be prepared that the situation around protests and public gatherings could change quickly, with the potential for significant violence, especially during unauthorised protests."