Belgium sought his arrest following a complaint filed in Brussels in 2011 by five former diamond mine slaves
A US-Belgian businessman accused of enslavement and diamond trafficking during Sierra Leone's civil war has died in a Brussels prison, officials said on Thursday.
Michel Desaedeleer, 65, "died on Tuesday to Wednesday night, most likely of natural causes," a spokesman for the Belgian prosecutor's office told AFP.
Desaedeleer was arrested in August 2015 at Malaga airport in southern Spain, attempting to reach the United States where he resided.
He was soon transferred to Belgium where he had been scheduled to appear before a judge next week to request release on bail pending trial.
Belgium sought his arrest following a complaint filed in Brussels in 2011 by five former diamond mine slaves.
They detailed alleged crimes in Sierra Leone's eastern district of Kono between 1999 and 2001.
"Blood diamonds" helped finance civil wars across Africa in the 1990s and often funded military dictatorships in the continent.
Desaedeleer's name was mentioned in a United Nations report on the trade in 2000.
It said he signed an agreement in 1999 with brutal Sierra Leone rebels allowing him to exploit diamond mines and ship the gems abroad via Liberia.
The gems were sold mainly in Antwerp, Belgium's second-biggest city and the heart of the global diamond trade for several centuries.
"Sadly, the victims of slavery in the diamond mines in Sierra Leone's Kono district ... will never fully achieve justice," said Civitas Maxima, a Geneva-based organisation that gives legal advice to victims of war crimes and has helped build a case against Desaedeleer.
"Nevertheless, the arrest of Michel Desaedeleer, his imprisonment and the fact that his trial was scheduled to commence in a few months represent a victory for the victims who courageously filed a complaint against him," it added.
Around 120,000 people died in Sierra Leone's 1991-2002 civil war