Rajiv Mohan Kulshrestha, a businessman from Delhi, was deported to India on Saturday.
Nineteen others, mostly British and South African nationals, from Gift of the Givers, a South African charity, were also deported to their respective countries.
The foreigners have been deported from China for illegally "watching video clips that advocate terrorism and religious extremism," the foreign affairs office in Ordos city in north China's Inner Mongolia Autonomous Region, where they were detained, said in the first detailed comment on the incident.
"According to the police investigation, the foreigners first watched a documentary in a hotel room. After some of them left, the rest proceeded to watch video clips advocating terrorism. Police later found similar videos stored in a cell phone belonging to Hoosain Ismail Jacobs, a South African national," state-run Xinhua news agency reported.
After that police detained nine of the 20 and allowed the rest to leave China.
The police detained five South Africans, three British nationals and an Indian national on July 11 in accordance with China's criminal law which stipulates punishment for "allegedly organising, leading or joining terrorist groups", the report said.
"All the detainees admitted to their illegal acts and repented. The police imposed a lenient sentence and had them deported on Saturday. The other 11 foreigners were deported on Wednesday," the report said.
After being notified, diplomats with relevant foreign embassies in China visited their nationals involved in the case, who had been accommodated properly, said the foreign affairs office of Ordos.
Indian Ambassador to China Ashok K Kantha said on Saturday that while the focus during the last few days was on getting Kulshrestha released, Indian Embassy has sought from China precise circumstances under which he was detained.
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