As atheist China shuts churches, Christians pray in secret

In a run-down block of flats in north Beijing, up flights of bare concrete stairs, you can hear them singing hymns behind a closed door.

Inside, nine people are gathered round a table, a wireless speaker playing.

Afterwards, they pray.

"We also entrust the people who are suffering for you in jail to you, Lord," Pastor Xu Yonghai says.

"We entrust Chinese churches which were shut down and are suffering for you into your hands."

This is one of the few spaces left for Christianity in China - Mr Xu's own small flat.

It's what's known as a home or underground church - one not sanctioned by the Chinese Communist Party.

Mr Xu set up the church in 1989, after the Tiananmen Square Massacre. He's been to prison or re-education through labour camps three times for his beliefs.

But these are the darkest days he's known, as the party stamps down on any version of religion that does not acknowledge its supremacy.

"We are loyal to God," Mr Xu tells Sky News.

"We hold up the love. We even love our enemies. But they focus on class struggle, they detain pastors. For them, the pastors are tools for imperialists to attack China."

"Of course, we all feel we have no religious freedom. This country has no freedom for religious faith"

China is officially an atheist state, with freedom of religion guaranteed in the constitution.

State-sanctioned churches do exist, but the power and glory belongs to the party.

Worshippers in these churches must register with the authorities, CCTV cameras keep watch.

Even the Bible is being retranslated by the government, to ensure what it calls "correct understanding" of the text.

"Our leader is God, we are following the God," Mr Xu says.

"But for them, their leader is government, they are following the government."

Over the last six months, more underground churches have been shut down.

In September, Beijing Zion Church in Beijing - one of the largest in the country - was closed by police. It had refused to install CCTV cameras.

In December, the Early Rain Covenant church in Chengdu, southwest China, was also closed in a raid: more than 100 of its members were arrested. Its pastor Wang Yi remains in custody.

In late March, the Shouwang Church in Beijing was also closed. Members were questioned by police.

The church pledged to hold a prayer meeting in a public square in Beijing.

We went along to observe.

But authorities had simply shut down the entire square, posting police officers at every entrance.

The few worshippers brave enough to attend were interviewed by police and then ushered away.

We were followed by undercover police, then approached.

One threatened revoking our Chinese visas if we continued to film.

Outside Pastor Xu's home is a small police station. He says it was constructed just to keep watch on him.

"We can't stop praying just because we are afraid of being jailed," he says.

"Compared with our predecessors, they were jailed for life or sentenced to death with reprieve. But they persisted.

"So will we."