Bible-preaching devices have turned up in a remote indigenous village, sparking fears that Christian missionary groups are targeting uncontacted and isolated tribes, despite strict bans.
According to reports, solar-powered devices with audio recitals of Biblical passages in Portuguese and Spanish have been spotted among the Korubo people.
The tribe, who live in the Javari valley, near the Brazil-Peru border, are under strict protection by the Brazilian government.
Military police stationed near the protected region have also reported mysterious drones flying overhead, according to a joint investigation by The Guardian and Brazilian newspaper O Globo.
Sgt Cardovan da Silva Soeiro said he was ordered to shoot them down but was unable to.
