Chinese local authorities have released all 18 house church leaders arrested in Langzhong city, Sichuan province, on June 9.

ChinaAid Association said they were released due to pressure from many supporters who called the Public Security Bureau (PSB) office after seeing ChinaAid's press release.

Thirteen of the leaders were detained for 10 days before being released on June 23.

More than 30 house church leaders were gathered in Pastor Li Ming's house church in Langzhong city when the arrests took place.

Several dozen officials in six to seven police vehicles from the local Domestic Security Protection Squad surrounded the site, before arresting all 30 of the Christians and searching the house. Police released 12 leaders the same day, but detained 18.

ChinaAid and the 18 released house church leaders have expressed their gratitude towards the Christians whose prayers and phone calls led to their release.

ChinaAid and other persecution watchdogs say house churches and their leaders continue to face persecution in China, an officially communist country.

Although China allows Christians to practise their faith, it believes the state should have ultimate control over the church.

The leaders of unregistered churches, meanwhile, say only God has authority over the church and its affairs.

There are believed to be at least 40 million house church members in China.