Reports from Indonesia's Papua region say police arrested 18 people for protesting outside the local legislative council in Jayapura last Monday.
The coordinator of the rally, Buchtar Tabuni, said he had sought police permission for the rally but was arrested.
They have since been released.
The demonstrators were calling for a review of the so called Act of Free Choice which took place in 1969 and formed the basis for Indonesia to take over the former Dutch colony in a process recognised by the United Nations.
Indonesian security forces reportedly blocked roads as hundreds of people poured into Jayapura to take part in the rally.