The persecution of Christian refugees living in a German reception centre has prompted drastic measures to reduce religiously-motivated violence, Open Doors reports.

The Christian persecution charity released on Monday a case study on a centre for refugees in Rotenburg, central Germany.

Researchers found that Christians living in the centre had faced death threats from Muslim refugees, and 'sentencing' by unofficial 'Sharia councils'.

On 10 July, a number of Christian refugees returned from church to find a notice in one of the rooms that said: "To all Muslims: now is the time to behead the unbelievers".

The Christians were temporarily moved to live in a local church to avoid attack.

One Iranian refugee told interviewers that one night a group of men shouted: "Whoever finds an Iranian woman today may rape and kill her. Kill them all. You may kill and rape them. You can do it, everywhere. Wherever you find them, you may do that."

"We came here to live a free life, but now we are being oppressed heavily," she said. "It is just like the Daesh [ISIS]: we feel very oppressed... I am living her under constant pressure and cannot take it any more. Nobody is allowed to know that I am a Christian, for I am afraid that they might find out about it in Iran. I am living under constant fear and oppression."

Another Iranian Christian said a Muslim woman had taken her Bible and tore it apart. "I fled from Iran because I want to live and now the same is happening to me here, again," she said. "I am living in fear here, in this accommodation, because again everybody is asking me: 'Why are you a Christian?' I fled from these attacks and now I have to live with it in such a confined space."

A third refugee recalled a death threat in June. "They told me: 'We are going to kill you! You are a Christian and you have left your religion,'" she said.

Open Doors recorded the testimonies of 32 refugees affected by religiously-motivated attacks in the Rotenburg centre, from countries including Iran, Syrian, Eritrea and Iraq. A number of them said that security staff at the centre had failed to take their concerns seriously, and that they were afraid to report incidents to the police.

The case study follows a wider report released by Open Doors earlier this month, which found that hundreds of Christian refugees had been beaten and sexually abused in German refugee camps.

A total of 743 Christians and 10 Yazidis were victims of religious motivated attacks in camps between February and September 2016, the report showed, but it warned the figure was the "tip of the iceberg".

It said "a number of unreported cases" must be assumed as only 17 per cent of refugees affected reported the incidents to the police because they feared their situation would become worse.

At the Rotenburg centre, however, steps have been taken to improve religious tensions. Christians have now been housed together in a separate part of the compound and Christian personnel have been hired to supervise Christian refugees.

"Since these changes were made, there have been no reports of religiously motivated attacks at the centre," Open Doors reports.