Amnesty International says the people of Papua in Indonesia must be allowed to express their views without harassment, threats or the fear of criminalisation.
The comments come after 3 deaths following rallies on May the 1st, marking the day that Indonesia controversially took control of the former Dutch colony.
Amnesty also says at least 22 people have been detained since the rallies.
The agency says it is does not take a position on the political status of Papua or any other province of Indonesia, but says Papuans should be free to peacefully express their views.
It says there should be a prompt, independent investigation into allegations that the unnecessary use of firearms by the security forces resulted in the 3 deaths and injuries to at least 7 others.