Michael, 49, was arrested in December 2014 after encouraging the church. Reith, 36, was arrested on Jan. 11, 2015 after submitting a letter from South Sudan Presbyterian Evangelical Church leaders inquiring about the whereabouts of Michael.

Christians called for prayers for the church leaders and other Christians arrested last week.

“Pray for them, because they are being persecuted because of Christ,” said one former church leader who fled the country due to persecution in 2011.

Police aboard five vehicles raided the compound of the evangelical school, which is owned by the SPEC.

Last year a court ruled that committees imposed on the church to enable Muslim investors to take it over were illegal.

Harassment, arrests and persecution of Christians have intensified since the secession of South Sudan in July 2011. The Sudanese Minister of Guidance and Endowments announced in April 2013 that no new licenses would be granted for building new churches in Sudan, citing a decrease in the South Sudanese population.

Sudan since 2012 has expelled foreign Christians and bulldozed church buildings on the pretext that they belonged to South Sudanese. Sudan fought a civil war with the South Sudanese from 1983 to 2005, and in June 2011, shortly before the secession of South Sudan the following month, the government began fighting a rebel group in the Nuba Mountains that has its roots in South Sudan.

Due to its treatment of Christians and other human rights violations, Sudan has been designated a Country of Particular Concern by the U.S. State Department since 1999, and the U.S. Commission on International Religious Freedom recommended the country remain on the list in its 2016 report.

Sudan ranked eighth on Christian support organization Open Doors’ 2016 World Watch List of countries where Christians face most persecution.