An extraordinary row has erupted over the removal by Norway's child welfare services of the five children of a Pentecostal Christian couple.

Marius Bodnariu is a Romanian married to Ruth, a Norwegian. Formerly members of the Philadelphia Pentecostal Church in Bucharest, they moved to Norway 10 years ago to start a family there and live in Naustdal on the west coast, north of Bergen.

According to a petition in support of the family which has attracted more than 22,600 signatures, the couple have been charged with "Christian radicalism and indoctrination".

According to Rev Cristian Ionescu, who has been backing the couple's campaign for the return of the children, on November 16 the welfare services, or Barnevernet, took the two oldest children from school without their parents' knowledge. Accompanied by police, they then appeared at the Bodnariu home and took the two older boys, leaving Ruth with three-month-old Ezekiel. The couple then visited the local police station to try to resolve the situation. The following day Barnevernet officials accompanied by four policemen, without any court orders or documentation, came to the Bodnarius' home and removed Ezekiel as well.

On Wednesday, November 18, Barnevernet notified Ruth that her children were separated into two families and that the children had already begun to integrate into their new lifestyle.

While the circumstances of the removal of the children appear extraordinary, Barnevernet has faced a long record of similar charges, particularly related to its treatment of the families of immigrants. In 2011 the children of an Indian couple, Anurup and Sagorika Bhattacharya, were removed from their care in a move that drew severe criticism from the Government of India. Also in 2011 the children of Eva Michaláková and husband, who originate from the Czech Republic, were removed, and in April 2015 a two-and-a-half month old girl called Maxine, whose mother is a deaf Norwegian and whose father is Slovak. One reason given was "lack of eye contact between girl and her parents".

According to a report by the Norwegian newspaper Aftenpost in May, 3,000 children of non-Norwegian parents are currently in the custody of Barnevernet. The reasons can vary from alleged child abuse to neglect but often involve charges of parents physically hitting their children – not alleged in the Bodnariu case – which is illegal in Norway. Parents cite cultural differences but diplomatic rows and media storms have broken in Russia, Latvia, Lithuania and Poland.

According to the NewsinEnglish.no website, Barnevernet is also criticised for placing young children outside their own language groups which mean that they quickly lose their native tongue.

A petition to Parliament launched by lawyers, psychologists and social workers in June said: "Society wants to be confident that Barnevernet operates with high professional competence and exercises good judgment ... but those of us involved in individual cases unfortunately see another reality all too often."

Barnevernet has been asked to comment on this story.