One of the leading legal defenders of China’s churches, Zhang Kai, was released from jail on Wednesday after being arrested in August 2015. Zhang posted on social media that he has returned to his home in Inner Mongolia. The human rights attorney has defended over 100 churches affected by a political campaign to demolish crosses, and sometimes whole buildings, in the Zhejiang province.

The political campaign is based on a clause in the Chinese constitution that claims to protect the freedom of religion, declaring that, “No state organ, public organization or individual may compel citizens to believe in, or not to believe in, any religion; nor may they discriminate against citizens because they do, or do not believe in religion. The state protects normal religious activities.” The Chinese Communist Party ruled that a church building that contained a cross that could be seen by the public was a violation of the clause.

Zhang Kai was arrested just before a meeting with David Saperstein, the U.S. ambassador for international religious freedom. Authorities charged him with “endangering state secrets” and “gathering a crowd to disturb the public,” which led to him being criminally detained. Zhang was subsequently sentenced to six months of residential surveillance at a “black jail,” where prisoners are held in solitary confinement at a secret location. In February, Zhang appeared on state television stating a “confession” that he had disrupted social order and endangering state security, but many believe that this confession was coerced. The terms of his release last Wednesday are still uncertain.

Zhang was, however, not the only activist who was targeted by the state, as China has been increasingly cracking down on official government churches and on human rights attorneys as seen this past year. While Zhang was lucky to have been released already, many other pastors and church staff arrested on similar grounds were given much harsher penalties. Pastor Bao Guohua of Holy Love Christian Church received a sentence of 14 years in prison, and his wife, Xing Wenxiang, 12 years, both charged and convicted of “corruption, financial crimes and gathering people to disturb social order.” Their son, Bao Chenxing, also received a three-year prison sentence.

Bao is one of eight pastors of the official Three-Self Patriotic Movement (TSPM) churches detained, including Gu Yuese, the pastor of China’s largest TSPM church, who was reportedly detained in a “black jail” on charges of corruption. Gu was detained after criticizing CCP policy in Zhejiang, where the government has already demolished the crosses of more than 1,800 churches.

Along with many other pastors, the government has also brought formal charges against nearly 20 human rights lawyers who have worked against the demolitions, and coerced “confessions” from several of them already.

Christian Solidarity Worldwide’s chief executive Mervyn Thomas has been fighting for those falsely accused during the campaign, and last week, after the release of Zhang, reiterated concerns that other human rights lawyers, along with Zhejiang pastors, remain in detention.

“We urge the Chinese government to protect the rights and safety of those who defend freedom of religion of belief and other human rights in China.”