Indonesian soldiers on trial for the alleged brutal abuse of two Papuans should be charged with torture rather than the minor offence of disobeying orders, Amnesty International said Saturday.

The three soldiers appeared Thursday before a military tribunal, after the online broadcast of a video showing the torture of unarmed men sparked an outcry.

But they were charged with disobedience to orders rather than more serious crimes such as illegal detention and abuse.

In the video, posted on YouTube last year, soldiers place a burning stick to the genitals of an unarmed man and threaten another with a knife as part of an interrogation about the location of weapons.

"Amnesty International urges the Indonesian authorities to ensure that the three soldiers... (are) tried in full criminal procedures for torture or similar crimes," Amnesty's Asia-Pacific Deputy Director Donna Guest said.

Military prosecutors have said they lacked evidence of torture because the victims would not testify, despite the existence of a CD of the video and detailed statements given by the victims to human rights groups.

According to the National Human Rights Commission, the victims would like to testify but were terrified of military reprisals, and had not received adequate safety guarantees.

"Amnesty International believes that the civilian courts are much more likely to ensure both prosecution for the crimes involving human rights violations and protection for witnesses than the military system," Guest said in a statement received by AFP.

Indonesia had pledged to rein in military abuses in regions such as Papua and the Maluku islands in return for renewed US military exchanges. The soldiers face a maximum sentence of two and half years in jail.