Nazi-era filmmaker Leni Riefenstahl has been injured in a helicopter crash in Sudan while making a film about her life.

The aircraft made a forced landing at El Obeid, 350 km (220 miles) southwest of the Sudanese capital, Khartoum, when returning from the Nuba mountains in central Sudan on Tuesday evening.

A German magazine reported last month that Ms Riefenstahl had been going to Sudan to visit the Nuba tribe for the first time in 23 years, accompanied by cameraman Horst Kettner, her longtime companion.

Ms Riefenstahl, 97, suffered two broken ribs in the crash, while Mr Kettner suffered leg and shoulder fractures and eye injuries.

Ms Riefenstahl is also reported to be suffering from bronchitis.

Both are due to be repatriated to Germany on Thursday.

Old friends

Last month, Ms Riefenstahl, who gained international fame and notoriety for her documentary films about the Nazis, said she wanted to trace Nuba friends despite the perils of the journey.

"Of course at my age it is not so easy and perhaps not completely without risk," she told Reuters news agency.

"My only goal is to find my Nuba friends again, and above all try to find a way to help them."

The Nuba, estimated to number one million, live as farmers and herders in a remote part of central Sudan which has been caught up in the government's 17-year war with southern rebels.

Ms Riefenstahl had ignored a security warning against going to the mountains to photograph Nuba wrestlers.

She was travelling under the assumed name of Mrs Jacob.

Propaganda

Ms Riefenstahl took widely acclaimed pictures of Nuba tribespeople during previous visits to Sudan.

But her return stirred controversy in Germany.

Critics said Khartoum's Islamist government, mired in civil war, would use the trip for propaganda - but Ms Riefenstahl rejected such claims.

"It is incomprehensible that my activities overall and that my plans to travel to Sudan in particular to help the Nuba would stir controversy," she said.

Ms Riefenstahl was shunned after World War II for making Nazi films such as "Triumph of the Will" and documentaries about the 1936 Berlin Olympics.

Sentenced to four years in prison after World War II for her part in Nazi propaganda, Ms Riefenstahl has often expressed irritation that she is tied with Nazi Germany in public memory.