It's reported authorities in the city of Guangzhou will give up to one thousand pounds for information.
It's part of a crackdown on illegal worship.
Elaine Pang, a British Chinese Christian attending church in London expressed her sadness on Premier's News Hour.
"To be honest, I'm not very surprised," she said. "There's a massive underground church network in China, as most Christians might know.
"I think it just shows how desperate the government are to crack down on religion in China.
"Over the five years that I lived in China it was really clear that money is really a force and motivation for a lot of things, whether that's in education, getting a job, bribery, all these kind of things.
"Now that they're using this kind of means to crack down on the churches, it's quite expected. I think it's sad, but not surprising."
Concern's also being raised by religious freedom charity Release International.
Spokesman Andrew Boyd has been speaking to believers in China.
He told Premier: "One Christian told our partners that there seems to be no solution now to having to meet in secret in that country and its registered churches that are also struggling.
"They said we have no solution. Many Christian brothers and sisters don't dare to worship together and must gather privately and in secret."
Over 100 members were detained in December last year. Reports last month suggested 11 were still in custody.
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.