FREETOWN, Sierra Leone - Prosecutors opened the first U.N.-backed war-crimes trial Thursday in the vicious 1991-2002 conflict in diamond-rich Sierra Leone, calling for "a just accounting for the agony of 10 long years."

Eleven suspects face trial in terror campaigns estimated to have claimed a half-million victims of killings, systematic mutilation and other atrocities. In a development that surprised even his defense team, the court's most-prominent detainee announced intention to act as his own attorney.

The tribunal is the first international war crimes court to try suspects in the country where the atrocities occurred. It is charged with prosecuting those most responsible for alleged war crimes and crimes against humanity in Sierra Leone.

Though 13 defendants are indicted, only nine are in custody and some of the most prominent suspects are dead or out of the court's reach.

The civil war for control of Sierra Leone and its diamond fields won notoriety for insurgents' trademark atrocity: using machetes to hack off the hands and feet of thousands of civilians.

"Tears of the maimed, the mutilated and the violated will dampen these walls," chief prosecutor David Crane, a former U.S. Defense Department lawyer, told judges and public during opening statements at the $3 million courthouse built for the trials.