15 Uzbek men have pleaded guilty to plotting a rebellion in the town of Andizhan last May.
The men's trial began today in the Supreme Court in the Uzbek capital, Tashkent.
Uzbekistan has said Islamist terrorists were responsible for the deaths of 187 people in Andizhan on 13 May. However, independent witnesses reported that troops opened fire on a crowd of protesters and killed hundreds of civilians.
The 15 men are the first of more than 100 people facing charges that include murder, mass unrest and an attempted coup. The trial is expected to last up to a month.
Human rights groups have accused Uzbek authorities of seeking to cover up a massacre of hundreds.
Amnesty International said the defendants are at risk of being executed 'following an unfair trial', while Human Rights Watch said the Uzbek government is trying to 'deny responsibility and silence witnesses'.
