Updated

Police arrested three Christian church leaders in a raid on a gathering at a private home in northeastern China, a U.S.-based monitoring group reported Wednesday.

About 30 policemen and officials from the local government's Religious Affairs Bureau took part in the Dec. 29 raid on the home in Duolun, in Inner Mongolia 250 kilometers (155 miles) north of Beijing, the China Aid Association reported.

The officials declared the service an "illegal gathering," the association said, a reflection of China's policy of permitting worship only in official churches whose clergy and activities are tightly controlled by the officially atheistic communist government.

Detained were Liu Guanghua, 42, Zhi Huiping, 41, and Zhi Ruiping, 35, the association said. It said the three women were being held at the Duolun County Detention Center.

Wednesday was an official holiday in China and calls to Duolun county government offices rang unanswered.

The association said the three women were sentenced to 15 days of administrative detention, a measure used against people deemed to have committed offenses but who are not legally recognized as criminals.

Activists in the unofficial church are frequently sentenced to up to three years in prison camps, part of a system called reeducation through labor that sidesteps the need for a criminal trial.

The association said the service had been part of post-Christmas celebrations, but didn't say how many people were attending.

While repression against unofficial church groups varies by region, the central government has enacted measures demanding such groups either register and accept government supervision, or face harsh punishment.

Yet with numbers of Christians growing across the country, millions still risk harassment and arrest by worshipping independently, often in private homes.

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