China is cracking down on churches with reports of pastors being arrested and congregations being shut down.
Release International said the crackdown on the Church is part of a "get-tough policy" on religion ordered by Chinese President Xi Jinping last December.
He is reported to have ordered that churches be forced to "adhere to Marxist religious views", and called for the stricter enforcement of religion laws.
"His aim is to bring China's religious minorities under ever-tighter state control," said Release International.
Release partner, ChinaAid, reports that members of Sunshine Reformed Church in Changchun, Jilin Province, were manhandled during a recent police raid on 21 August.
According to ChinaAid, the pastor, his wife and seven elders were taken away by police, and two women were beaten unconscious during the incident.
Release International, which supports persecuted Christians worldwide, said the incident revealed the "ferocity" with which police raids are being carried out.
"It's all about control," said Release CEO, Paul Robinson.
"What the party cannot dominate and control it seeks to eliminate. And it's getting worse. Our partners tell us that churches in China are facing the toughest persecution since the Cultural Revolution."
More police raids have been carried out on churches in Beijing and the provinces of Shaanxi, Sichuan and Shanxi.
Local Christians believe that the Chinese President's goal is to bring all Protestant Christians into the government-controlled Three-Self Church or else risk being arrested and having their unregistered church closed down.
In another incident, around 100 armed police officers are reported to have surrounded Christians attending a family summer camp in Shanxi province. Some adults were detained and police searched the homes of several church members involved in the event. They had their Christian books and documents seized.
The reports coincide with heightened concern at the UN about China's treatment of the mostly Muslim Uyghur minority.
The UN has accused China of possible crimes against humanity against the Uyghurs and said it has "credible evidence" of torture.
Although most Uyghurs are Muslim, some are Christian like Pastor Alimujiang Yimiti who was jailed for 15 years for 'inciting separatism' and 'leaking state secrets' after telling a colleague on the phone that citizens were being monitored by state security.
Release reports that in prison, Pastor Yimiti is being forced to listen to Communist propaganda through headphones.
Release International has launched an appeal to help Christians fleeing persecution. One of them is pastor, Dong Zhao, who fled China with his family in September 2021 after experiencing persecution that included barring his children from attending school. After 195 days on the road and travelling over 18,890 miles, passing through 11 countries, they made it to the US.
"There are many Christians like Dong, who are suffering intense persecution in countries such as China, Iran, Pakistan and Eritrea," said Mr Robinson.
"Many see themselves as having no option but to run for their lives and try to make a new beginning in another country.
"Release is working with partners on the ground to help these Christians who are forced to leave – and those who are determined to stay."