Reports from Papua New Guinea say seven people were locked up in police cells for demonstrating for West Papua at the start of a visit of the Indonesian president, Joko Widodo.
NBC reports that they were held for six hours after they waved placards and the West Papuans' Morning Star flag.
Indonesia has banned the flag and some people have been jailed for several years for displaying it.
President Widodo arrived from West Papua where he at the weekend released five political prisoners, who had been jailed since 2003.
He also said he would open the area to foreign media.