Chinese officials reportedly arrested an elderly bishop of the underground Catholic Church last week.

Coadjutor Bishop Augustine Cui Tai of Xuanhua, 70 years old, was taken by Chinese officials to an undisclosed location according to local Catholics, UCA News reported on Sunday. Bishop Cui has been under house arrest since 2007.

During his period of house arrest, Bishop Cui has been periodically detained and released by authorities including an arrest in March of 2019 by Heibei province officials. He was released in January of 2020, and reportedly arrested again on June 19.

Cui was ordained a bishop in 2013, since then he has served as coadjutor to Bishop Thomas Zhao Duomo of Xuanhua, who is 96 years old. According to a 2019 report by AsiaNews, Cui has been repeatedly detained, and spent periods in forced labor camps, for engaging in evangelization activities without government authorization. He has also spoken out against the state-sponsored Catholic Church in China, saying it is building a Church “independent” of the Holy See.

The news of Bishop Cui’s arrest comes as the 2018 Vatican-China agreement on the ordination of bishops is set to expire in September. The Vatican reportedly hoped the agreement would help unify the underground Catholic Church in China—which had remained in full communion with the Holy See—and the Chinese Patriotic Catholic Association which was the state-sponsored Church.

Following the agreement, and in line with the Communist government’s program of “sinicization,” state officials in different regions of the country have continued to remove crosses and demolish church buildings and underground Catholics and clergy continue to report harassment and detention.

The Congressional-Executive Commission on China, in its 2019 annual report, listed Bishop Cui’s 2019 arrest as an example of why some observers believed the Chinese Communist Party’s (CCP) persecution of the Church actually intensified after the agreement.

However, Archbishop Claudio Maria Celli, who was involved in the crafting of the agreement, said on June 7 that he believed the agreement should be renewed for “one or two years”. The full text and terms of the Vatican-China deal have not been published.

Religious freedom advocates have warned that the CCP has waged a forceful campaign to bring religion under its control through the process of “sinicization,” where religion would purportedly be in harmony with the state’s interpretation of Chinese culture.

“It is undeniable that they are still situations that still require a journey,” Archbishop Celli, a long-serving Vatican diplomat, said on June 7. He wished that the agreement could eventually bring about an environment “in which a Chinese Catholic can express all of his fidelity to the Gospel and also with respect for his being Chinese.”

Vatican Secretary of State Cardinal Pietro Parolin, who also played a key role in the agreement, said in 2019 that “inculturation” with Chinese culture and “sinicization” can be “complementary” and “can open avenues for dialogue.”

On May 24, Pope Francis led a Day of Prayer for the Church in China and entrusted China to the Blessed Virgin Mary.

“Dearest Catholic brothers and sisters in China, I wish to assure you that the universal Church, of which you are an integral part, shares your hopes and supports you in your trials,” he said.

“She accompanies you with prayer for a new outpouring of the Holy Spirit, so that the light and beauty of the Gospel might shine in you as the power of God for the salvation of those who believe.”