Afghanistan says it will deport hundreds of South Korean evangelical Christians amid fears for their safety.
The group says that it is working to improve medicine and education
They have been accused by Islamic clerics of preaching Christianity. Afghanistan bans attempts to convert people to non-Islamic faiths.
Around 1,500 South Koreans arrived this week for a "peace festival", and education and entertainment programme.
On Wednesday, hundreds of Afghans held a protest rally against them at a mosque in the city of Mazar-e-Sharif.
"They were given tourist visas and now it seems they are misusing their tourist visas," a government official told the AFP news agency.
"The risk of them becoming a target is very high," he said.
Religion is a sensitive issue in Afghanistan
Correspondents say that the Seoul government has repeatedly urged the Christians - among them 600 children - to return home, warning of the dangers they face at the hands of the radical Taleban movement.
A spokesman for the South Korean-based Institute of Asian Culture and Development (IACD) told AFP that they are only in the country to provide war-ravaged Afghanistan with medical, education and cultural programmes.
He said they were in the capital and four other towns and cities.
"We are not against the policies of Afghanistan. We respect and we love Afghanistan," he said.
In February several thousand people protested against the release of a man who converted to Christianity, demanding he face the death penalty. He was spirited out of the country.