Seven women teachers were being held in detention in the northwest province of Xinjiang after police raided a house church where children were attending religious classes earlier this month, a rights group said on Wednesday.
According to US-based ChinaAid, police first rounded up 70 children and their teachers for questioning.
“The children were attending special summer classes arranged by the house church in the regional capital city of Urumqi when the police action occurred on the morning of July 2... Some of the children’s parents and school principals and teachers were also summoned and questioned,” the organisation said in a statement.
"To prevent children from having access to religious education in the faith of their parents is a direct contravention of the UN Declaration on the Elimination of All Forms of Intolerance and of Discrimination Based on Religion or Belief (1981) and U.N. Convention on the Rights of the Child (1989) which was adopted by China in 1992,” said Bob Fu, ChinaAid chief.
There was no word from the government about the incident.
The news of the raid comes a day after authorities in Shanghai allegedly detained a bishop newly-ordained by the Vatican.
Thaddeus Ma Daqin quit his post in the state-run Catholic Patriotic Association which supervises the church in China but is not recognised by the Vatican.
Reports said Ma was taken away by officials after he publicly quit the post he held in the government body.
According to Reuters news agency, Chinese Catholics number between 8-12 million, and are divided between a state-sanctioned church that has installed bishops without Vatican approval and an "underground" wing long wary of associating with the Communist Party-run church.
The relationship between Beijing and the Vatican has been tense recently.
Last week, the State Administration for Religious Affairs (SARA) urged the Vatican to rescind its threats to excommunicate two Chinese bishops, who were to be ordained without papal approval, and return to the "correct path of dialogue."
The threats of excommunication are "extremely unreasonable and rude," a SARA spokesperson said in a statement.
On Tuesday, the Vatican said it refused to recognise the ordination on July 6 of Reverend Joseph Yue Fusheng in Harbin, saying his elevation by Beijing's state-run Church overseer had not been blessed by the pope.
“All Catholics in China, pastors, priests, consecrated persons and lay faithful, are called to defend and safeguard that which pertains to the doctrine and tradition of the Church," the Vatican said in a statement.