A Sudanese pastor has been found innocent of charges that he had obstructed a court-ordered demolition of his church in Khartoum.

Pastor Hafiz Mengisto of Khartoum Bahri Evangelical Church, along with lawyer Mohaned Mustafa, had challenged engineers who tried to take down a building not mentioned in the court order on July 1 last year. The two were arrested, and their trial began on December 14.

The case against Mustafa was dismissed on December 23, and against Mengisto on December 29.

Christian Solidarity Worldwide (CSW) has welcomed the men's acquittal, but said it remains "deeply concerned by the State's repressive actions against religious minorities in Sudan". Mengisto suffered head injuries while in police custody, and the head of discipleship at his church, Talahon Nigosi Kassa Ratta, remains in custody after being arrested on 14 December.

Two other pastors of a different denomination, Rev Kwa Shamal and Rev Hassan Abduraheem of the Sudan Church of Christ, were also arrested on 19 December.

CSW's Chief Executive Mervyn Thomas has called for their immediate release. "Their detention without charge is in clear violation of their right to liberty and security of person as detailed in article 9 of the International Covenant on Civil and Political Rights (ICCPR), to which Sudan is a party," he said.

Thomas urged the African Union to hold Sudan to account in its constitutional guarantees of religious freedom.

The Khartoum Bahri Evangelical Church was where Rev Yat Michael, a South Sudanese pastor who faced trial for espionage last year, once spoke out against the persecution of Christians in Sudan.

Michael and another pastor, Rev Peter Yeith, were eventually found not guilty of six charges, including "offending Islamic beliefs", promoting hatred amongst sects and undermining the constitutional system, and were released in August 2014. According to Release International, they had also opposed government attempts to sell off church property.

According to the US Commission on International Religious Freedom, the Sudanese government "continues to engage in systematic, ongoing, and egregious violations of freedom of religion or belief." Designated by the Commission as a 'country of particular concern' since 1999, Sudan's population is over 97 per cent Muslim, and the country's criminal code restricts religious freedom for all citizens. It also imposes Shariah Law on Muslims and Christians, allowing the death penalty for apostasy, stoning for adultery and prison sentences for blasphemy.

The USCIRF's 2015 report also notes the use of government policies and societal pressure to promote conversion to Islam. It is "impossible" to obtain permission to build churches, while their destruction has increased over the past four years.