A military tribunal in Ivory Coast on Thursday sentenced three senior military officials to life in prison for the 2002 murder of former junta leader turned president Robert Guei, and handed out lesser terms to others.

The sentencing ends a three-week trial in the Ivory Coast, the economic powerhouse of francophone West Africa, which has been going through a reconciliation process after more than a decade of political turmoil.

Guei was named head of state after a coup d'etat in 1999 but lost an election to Laurent Gbagbo a year later. He had been out of office for nearly two years when his bullet-riddled body was discovered on a roadside in the commercial capital, Abidjan, during a second attempted coup in 2002.

The three high-ranking soldiers close to Gbagbo who received life sentences were Dogbo Ble, commander of the Republican Guard, gendarmerie Captain Anselme Seka Yapo and another officer named as Sery Daleba.

At least five others received 10 years in prison as accessories to the killing.

Lawyers for the defendants said they would appeal the verdicts.

Dogbo Ble is already serving 15 years in prison for a 2012 conviction for complicity in violence including murder. Yapo was given a 20-year sentence for murder and assault last August.

Although the 2002 coup attempt failed, the non-commissioned officers behind it maintained their grip on the northern half of the world's top cocoa grower, eventually becoming the New Forces rebellion.

The group helped bring to power the current president, Alassane Ouattara, after Gbagbo refused to accept his defeat in a 2010 run-off election, triggering a brief civil war.

Gbagbo's trial before the International Criminal Court for alleged crimes against humanity committed during the conflict opened last month in The Hague.