Thunberg was detained while protesting at the opencast coal mine of Garzweiler 2, some 9 kilometres (5.6 miles) from Luetzerath.

Thunberg, who joined the protesters on Friday, was seen sitting alone in a large police bus after having been detained, a Reuters witness said.

(Reporting by Wolfgang Rattay; Writing by Riham Alkousaa; Editing by Maria Sheahan)