Zimbabwe authorities arrested six Christians on Friday, who were working as a part of a medical mission in the African nation.

Four of the group arrested are from the Allen Temple Aids ministry in Oakland, California, and include a doctor, two nurses and a community volunteer. The health workers, along with two Zimbabweans were scheduled to appear in court on Monday.

"They operated from two clinics, one in Mutoko and one in Harare, where they worked primarily with Aids orphans and HIV positive patients for the past decade," the American embassy said in a statement.

"We have picked up the six for questioning in connection with practicing without a premises' licence and dispensing medicines without the supervision of a pharmacist," a police spokesman told the state-controlled Herald newspaper.

A minister at their church said it has operated a home for Aids orphans for years, and this is the first time licensing has been an issue.