Zion Church, founded by pastor Jin Mingri in 2007, is one of China's largest underground church networks.

Zion Church, founded by pastor Jin Mingri in 2007, is one of China's largest underground church networks.

Leaders of the underground Christian Zion Church in China have been arrested, including pastor Ezra Jin, and the State Department has demanded their release.

The Zion Church is not recognized by the Chinese government. Its founder, Pastor Jin Mingri, and at least 20 other clergy members from his movement have been detained.

Activists say the unprecedented round-up could be the beginning of a wider crackdown on China's underground churches.