It's 57 years since the Papuan Morning Star flag was first flown officially when the indigenous people of the former Dutch New Guinea declared independence.
Demonstrations to mark the anniversary occur annually in Papua region, other parts of Indonesia, and in cities around the world.
Indonesian police and security forces were out in large numbers to crack down on the demonstrations which have grown in recent years in non-Papuan cities.
Dozens of demonstrators, not restricted to Papuans, were arrested in each event in cities including Kupang, Ambon, Surabaya and Ternate.
In Ternate, around a hundred are reported to have been taken into custody.
Demonstrators in Jakarta and Yogyakarta faced opposition by security forces.
In Surabaya, hundreds of West Papuan students were met with violent opposition by nationalist paramilitary forces, leaving around sixteen demonstrators injured.
Meanwhile, there were the usual high numbers of arrests over demonstrations in the urban centres of Papua and West Papua.
Around 80 people are reported to have been arrested in Papua's provincial capital Jayapura, where the headquarters of one of the main pro-independence organisations, the West Papua National Committee, or KNPB, was raided.
Premises of the KNPB's secretariat were also targetted by security forces in several Papuan cities or towns, including Timika, Sorong and Asmat.
This follows recent raids by police on KNPB activities in Jayapura.
Demonstrations to mark the anniversary were also held in several cities in Australia and New Zealand.
1961's declaration of Papuan independence was the following year eclipsed by a US-brokered agreement between the Dutch and Jakarta which paved the way for an Indonesian takeover.
The Morning Star flag is outlawed in Indonesia, and Papuans caught raising it publicly have been given prison sentences of up to fifteen years.
Photo caption: Executives of West Papua National Committee