Johannesburg - The Department of International Relations and Co-operation (Dirco) on Tuesday said it was in contact with some of the relatives of the 10 South Africans arrested in China.
Department spokesperson Nelson Kgwete said they had received news of the arrests on Sunday and that it had been confirmed by the Chinese authorities.
While the charges against the group were unclear, the South African embassy in Beijing was expected to handle the matter.
The arrest of the 10 came to light on Tuesday, following a statement from the Gift of the Givers.
The humanitarian organisation said the South Africans had been arrested without charge in China, having been part of a 20-strong tour group detained by Chinese officials last week.
The tour group were on a planned 47-day trip to explore the country, and was made up of 10 South Africans, nine British nationals and one Indian national, Gift of the Givers founder Imtiaz Sooliman said in a statement.
The tour "went horribly wrong" on Friday, when the group were arrested at Erdos airport, in Inner Mongolia, at 09:40 local time.
"No reasons were given for the arrest; cellphones were confiscated, there was no access to the embassies of origin, nor to their families. They were detained without charge, with no access to any communication nor to legal representation. "
He said that only on Sunday did the tour operator realise something was wrong, with news of the arrests only emerging after the operator went to Erdos.
Sooliman said the Chinese linked some members of the tour group to a banned organisation, a terror group, and for watching propaganda videos in their hotel room.
"Ironically, one of the arrested is an MK veteran of the Luthuli detachment who spent 27 years in exile. Dirco was contacted on Sunday and immediately consular services were provided, both in South Africa and China," he said.
"A team from the South African Embassy and the British Embassy met with the Chinese Foreign Ministry officials this [Tuesday] morning."
Remain in detention
Chinese authorities have since agreed to release 11 of the tour party, but they would remain in detention without charge until flights out of China could be found for them. Friday is apparently the earliest that this will be possible.
The other nine are being held without charge at a detention centre on the accusation that they were watching propaganda videos. They are five South Africans, three Britons and one Indian national, Sooliman said.
"Of the five South Africans being held, three [including the MK member] are direct relatives of Shameel Joosub, CEO of Vodacom. Salim Aziz Joosub, Shameel's brother, is CEO of Capital and Financial Brokers."
Sooliman said the families thanked the South African government for their "unwavering support and call upon the Chinese government to release the detainees immediately".
"These individuals have no terror links, no criminal record in their country and include Dr Feroz Suliman, a general surgeon at Waterfall Hospital, and his wife, Dr Shehnaaz Mohamed, also a medical doctor."
While the South Africans are locked in detention, the Chinese government is hosting Deputy President Cyril Ramaphosa, who arrived in the country on Monday.
In a statement on Monday, the Presidency said the deputy president was leading a South African government, business, and state-owned enterprises delegation on an official visit to the country, scheduled to end on Friday.