Thai authorities have charged eight Muslims with treason, saying they were key figures in a campaign of violence in the country's south.
More than 600 people have been killed in clashes in Thailand's largely Muslim south since January last year.
The men, who officials say belong to an outlawed separatist group, face death by lethal injection if found guilty.
All eight defendants, who work as teachers in Islamic schools, deny the charges against them.
The teachers stand accused of training young men to kill civilians, attack troops and set fire to schools and government buildings.
Thai Prime Minister Thaksin Shinawatra has described the men as significant ringleaders in the insurgency.
"They have ambushed officials, killed monks, teachers and students, set fire to schools and other government buildings, and stolen weapons," the prosecution said in a statement, according to Reuters.
The government has been criticised for its heavy-handed tactics towards the insurgents.
I wonder if the BBC ever considered whether the insurgents who have "ambushed officials, killed monks, teachers and students, set fire to schools and other government buildings, and stolen weapons," are using heavy handed tactics to achieve their objectives.