A total of twelve men were arrested on 13th October by the National Intelligence and Security Service (NISS) whilst they were meeting at the home of a church leader in Nyala, South Darfur.
Three of the men were released without charge after two hours of questioning.
According to Christian Solidarity Worldwide (CSW), the remaining men were tortured and pressured to renounce their faith while in custody.
CSW's chief executive Mervyn Thomas said in a statement: "We are alarmed by the arrest and torture of Christians in Darfur.
"The men, who were peacefully gathered in a private place and posed no threat to the state, were subjected to serious mistreatment and forced to renounce their faith."
Eight of the men were released on bail eight days after - only once they agreed to the demands of the NISS officers and were charged with public nuisance. At least four men required medical treatment.
The church leader was also arrested and remained in custody for a day longer as he refused to renounce his faith and was charged with apostasy under article 126 of Sudan's Criminal Code.
He has been released on bail but is required to report periodically to NISS.
Thomas said the case raised concerns over the protection of freedom of religion or belief for both Christians and other religious minorities in the capital Darfur.
He added: "We call for the charges against the men to be dropped immediately and without condition.
"This case stands out as a particularly serious and calculated violation of individual rights, and highlights the National Intelligence and Security Service's habitual use of torture."
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.
