Kinshasa - Democratic Republic of Congo President Joseph Kabila's chief adviser was killed and his finance minister seriously injured in an airplane crash near the eastern town of Bukavu on Sunday, 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 US 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 spokesperson Lambert Mende said the plane's pilot had also died in the crash.

He confirmed Katumba's death, saying: “It's a very big loss, he was considered a pillar of the presidential majority.”

Lambert said Finance Minister Matata Ponyo Mapon and roving ambassador Antoine Ghonda were “heavily wounded” in the crash and Marcellin Cishambo Rohuya, governor of the local South Kivu province, was lightly injured.

No official death toll was immediately available and details of the crash were patchy. A United Nations spokesperson said the small plane appeared to have overshot the runway.

“I don't have the number (of passengers) but according to our people in South Kivu the pilot landed in the middle of the strip, and went over the end,” said Alexandre Essome, spokesperson for the United Nations mission MONUSCO in the eastern town of Goma, from where the plane had taken off.

Ponyo is seen as an effective operator despite snags over the recent introduction of VAT tax which saw confusion and a sharp jump in inflation. His goal was to bring annual inflation down to nine percent in 2012 from 15 percent last year. - Reuters