Democratic Republic of Congo President Joseph Kabila's chief adviser was killed and his finance minister injured in an airplane crash near the eastern town of Bukavu Sunday, government officials said.
The accident, the latest in a country with one of the world's worst air safety records, comes as Kabila braces for negotiations to form a new coalition government after his disputed victory in a chaotic election in November.
Adviser Augustin Katumba Mwanke, 58, was regarded by many as the power behind the throne, according to a leaked 2009 U.S. diplomatic cable. He was a former governor of the copper-rich province of Katanga and retained major influence in the country's minerals sector.
Summing up Katumba's power, one Congolese senator said on condition of anonymity: If you wanted to negotiate business and Kabila said 'yes', that was 50 percent, but if Katumba said 'yes', that was 100 percent.
Government spokesman Lambert Mende confirmed Katumba's death, saying: It's a very big loss, he was considered a pillar of the presidential majority.
Four others died in the crash - both American pilots and two people who were hit by the wreckage - Deputy Prime Minister Adolphe Lumanu told reporters.
Lumanu said Finance Minister Matata Ponyo Mapon, roving ambassador Antoine Ghonda and South Kivu governor Marcellin Chisambo Rohuya were also hurt, although their injuries did not appear to be life threatening.
Government spokesman Lambert earlier said the finance minister and Ghonda had been heavily wounded in the crash.
A United Nations spokesman earlier said the plane appeared to have overshot the runway.
The plane ended up in a ravine where there are fields, there are two bodies still lying under the plane, Lumanu said.
The plane was a privately owned Gulfstream jet, said Lumanu, who was speaking after a crisis meeting of high ranking members of Kabila's political movement in the capital Kinshasa.
Katumba was seen as someone who pushed for power to be held by an inner circle around Kabila and his demise is an unpredictable new element in forthcoming coalition talks with opposition parties who rejected Kabila's poll victory as fraudulent.
It could also herald major changes in the way Congo handles it huge resources, ranging from copper to gold, oil, diamonds and tin, and in the way it conducts business with international donors and investors.
The 2009 diplomatic cable released by WikiLeaks noted that Katumba had been blamed within the government for bad press surrounding a $9 billion mines-for-infrastructure deal with China. The deal, criticised by the International Monetary Fund and others for selling the country's assets short, was eventually revised down to $6 billion in volume.
He had earlier been named in a 2002 report by the U.N. monitoring Group of Experts as being part of an organization that illegally seized control of billions of dollars' worth of state mining assets. He was briefly suspended from government following the report.
Kabila has been in power since a 2006 vote that drew a line under years of war and chaos in the central African country. But progress in developing its wealth has been slow and critics say corruption remains rampant.
Kabila was inaugurated for a new term in December despite broad misgivings over the November 28 poll, which was marred by bad organization and evidence of irregularities that sparked protests. Human Rights Watch said at least 24 people have been killed by security forces since results were announced.
Kabila's ruling party has also emerged in the lead from parliamentary elections held on the same day, but it won fewer seats than it had before, complicating the president's task of forming a solid coalition government.
(Additional reporting by Bienvenu-Marie Bakumanya in Kinshasa and Mark John in Dakar; Writing by Mark John; Editing by Ben Harding and Alessandra Rizzo)