Indonesia has started the trial of five pro-independence Papuans amid calls from human rights groups to cease proceedings.

The five Papuan activists are on trial in a court in Jayapura, capital of the isolated Indonesian province of Papua on the western end of the island New Guinea.

Both Papua and the neighboring province of West Papua have strong independence movements.

The five men on trial face treason charges for allegedly raising the outlawed Morning Star Papuan independence flag in October and calling for independence for the region, a report by The Jakarta Post newspaper said.

But Human Rights Watch, based in New York, said the men were peacefully demonstrating and it has called for the trial to stop.

"The Indonesian government should show its commitment to peaceful expression by dropping the charges against these five Papuan activists," Elaine Pearson, deputy Asia director at Human Rights Watch, said in a statement on the group's Web site.

"It is appalling that a modern democratic nation such as Indonesia continues to lock people up for organizing a demonstration and expressing controversial (opinions)."

Human Rights Watch also claimed that security forces used excessive force to disperse the three-day Papuan People's Congress gathering in Jayapura and three people died in the clashes.

Clashes between demonstrators and police began after one of the leaders read out a declaration of independence statement, Human Rights Watch said. "Police and the army fired warning shots to disperse the approximately 1,000 Papuans gathered for the peaceful demonstration," the group said.

Witnesses said security forces used batons and firearms against demonstrators, killing at least three and injuring more than 90 others.

Local authorities gave written warnings to eight officers, including Jayapura Police Chief Imam Setiawan, for not doing enough to protect civilians.

"However, no other action was taken against police or military personnel for possible misuse of force," Human Rights Watch said on its Web site.

Human Rights Watch also said it "takes no position on claims to self-determination in Indonesia" but upholds people's right "to express their political views peacefully without fear of arrest or other forms of reprisal."

Papua and West Papua together are about the size of Spain and occupy the western half of the island of Papua. The state of Papua New Guinea occupies the eastern half.

The two provinces have been a part of the Indonesian archipelago federation since the Dutch gave up colonial rule. A slim majority of Papuans in a controversial referendum in 1969 voted in favor of joining Indonesia but various separatist movements have been pushing for independence.

Papuans are ethnically Melanesian and closer to Australia's aborigines than the Asians who make up most of Indonesia's population. Papuans say their culture and identity is being eroded by an influx of Asian Indonesians.

Papua and West Papua are the poorest regions in Indonesia but are extremely rich in natural resources. Separatist Papuan leaders claim few of the region's population get a fair share of the wealth when the resources are exploited, often by international companies.

Many demonstrations in the two provinces are peaceful but there have been bloody clashes between more extreme group separatist groups. In early December, a half-hour gun battle with rebels in the Puncak Jaya highland area of Papua province left two policemen dead.

A week before the gun battle, pro independence rallies in parts of West Papua turned violent. Activists and pro-Papuan independence groups alleged that police and paramilitaries shot four civilians after hundreds of people attended religious services in Timika, a city on the southern coast of West Papua.

The celebrations were to mark the 50th anniversary of the region's self-declaration of independence. Hundreds of people took the streets, many in traditional dress, waving the Morning Star flag and cheering for independence, a report by the Australian Broadcasting Corp. said at the time.