A UN-backed war crimes tribunal in Sierra Leone has begun hearing the first cases against members of the rebel Revolutionary United Front.
The tribunal's legitimacy is being questioned by the rebels
The RUF is blamed for killings, rapes and abductions during a decade of civil war that ended in 2002.
But the first three defendants - who include the RUF's final military leader Issa Sesay - are refusing to acknowledge the court's legitimacy.
About 50,000 people were killed, and many more maimed and raped in the war.
The RUF's internal security chief, Augustine Gbao, and a key battlefield commander, Morris Kallon, are on trial alongside Mr Sesay.
The RUF's campaign of violence included hacking off the limbs of civilians as a trademark act of terror.
The BBC's Lansana Fofana in Freetown says that Mr Sesay occasionally lowered his head as the 18 war crimes charges, including sexual slavery, murder, looting and terrorising civilians, were read out.
Chief Prosecutor David Crane said that atrocities were committed in virtually all parts of Sierra Leone.
"This is the day I have been waiting for," said one amputee.
"I am now satisfied that someone is being held accountable for what the rebels did to me."
But correspondents say the tribunal's importance has been diminished by the deaths of RUF leader Foday Sankoh his deputy Sam Bockarie - best known under his nom de guerre Mosquito.
The tribunal has not yet been able to arrest the man accused of being the RUF's paymaster, former Liberian President Charles Taylor.
Despite being indicted on 17 charges of war crimes or crimes against humanity, Mr Taylor is living a life of luxury in exile in Nigeria.
Unlike the war crimes tribunals for Rwanda and the former Yugoslavia, the court is based where the alleged crimes occurred and draws on both national and international law.