Ten Sudanese Christians released on Sunday were beaten while in captivity, according to World Watch Monitor (WWM.

They were part of a group of 13 taken from the home they shared in Nyala, southwest Darfur, in October. Three were released shortly after their arrest.

A source told WWM they had faced 'severe pressure' over their faith and that it was not clear whether they would face further prosecution.

Sudan is fourth on the 2018 Open Doors World Watch List of the 50 countries where it is most difficult to live as a Christian.

Christians face a range of discriminatory practices. Church buildings have been demolished or expropriated by government agencies and church leaders have been arrested, fined and imprisoned.

The European Union's special envoy for Freedom of Religion or Belief, Ján Figel, has repeatedly spoken out on behalf of Christians in Sudan. After a visit to Khartoum in March last year he told World Watch Monitor he had 'reminded the authorities about the importance of upholding freedom of religion or belief as in the constitution and recommended the construction of a civil state based on equal citizenship for all'.

Amnesty International's 2017/18 report said: 'Security forces targeted opposition party members, human rights defenders, students and political activists for arbitrary arrest, detention and other abuses. The rights to freedom of expression, association and peaceful assembly were arbitrarily restricted. The security and humanitarian situation in Darfur, Blue Nile and South Kordofan states remained dire, with widespread violations of international humanitarian and human rights law.'