Five clergy members of China's underground Roman Catholic church were detained on 1 July in a city west of Beijing, a U.S. based religous group said on 5.

The clergy memebers were detained when they were on their way to visit the Rev. Lu Genjun, who was released recently from a labor camp, said the Cardinal Kung Foundation.

The foundation said no other details.

The government of China has been persecuting religious groups and only allowing state-monitored worship. So underground churches and their members often get arrested and harassed. However, an unofficial statistic report says there are more than 12 million believers who attends unregistered underground churches and house churches. This number is much larger than some 4 millin for China's officially sanctioned church.

The communist government ordered Catholics to break ties with the Vatican in 1951. So the Chinese Patriotic Catholic Association which is a government-authorized organization, doesn't recognize papal authority.

The Kung Foundation identified those detained: the Revs. Kang Fuliang, Chen Guozhen, Pang Guangzhao and Joseph Yin and Deacon Wang Li Jun, AP reported.