Chinese authorities arrested a group of 20 foreign tourists from the U.K., South Africa and India, on suspicion of links to a “terror group,” a relative told the Associated Press (AP) on Wednesday. Some of those arrested were reportedly watching propaganda videos from a terrorist group in their hotel rooms.

Nine people were criminally detained and can be held for up to 37 days by police while investigations continue, China's foreign ministry said Wednesday. The country agreed to release 11 of the tourists arrested, South African charity Gift of the Givers Foundation, said, in a statement on its Facebook page, Tuesday. All of those arrested were traveling in China as part of a single group.

The nine people who will reportedly be held at a detention center in Inner Mongolia include five South Africans, three Britons and one Indian national. The British embassy in Beijing confirmed that nine Britons and two dual British-South African nationals had been detained, and six of them had been deported.

"Consular staff have visited the group to provide assistance and we are liaising with Chinese authorities," a British Foreign Office spokesman told Reuters.

The group was on a 47-day tour of the country when they were detained Friday at an airport on suspicion of committing crimes in Ordos in Inner Mongolia region.

“No reasons were given for the arrest, cellphones were confiscated, there was no access to the embassies of origin nor to their families,” Gift of the Givers Foundation said. “They were detained without charge with no access to any communication nor to legal representation.”

The charity also said that several of those detained are relatives of Shameel Joosub, CEO of South African telecommunications company Vodacom. "My family and I are deeply concerned for the safety and well-being of my brother, aunt and uncle," Joosub said, in an emailed statement to AP.