Gen Nyamwasa has been living in exile in South Africa since February
The former chief of staff of the Rwandan army has been
shot in South Africa and taken to a Johannesburg hospital in a critical
condition.
Gen Faustin Kayumba Nyamwasa, a critic of President Paul Kagame, fled from
Kigali in February.
His wife told the BBC the couple had been returning from shopping when a
gunman opened fire on the car.
She said she was certain it was an assassination attempt as since there was no
demand or money or any goods.
He is now undergoing surgery, she said.
BBC Africa analyst Martin Plaut says Gen Nyamwasa was one of President
Kagame's closest confidants, until they fell out.
Since arriving in South Africa the former army chief has accused the president
of corruption, accusations the Rwandan authorities have denied, he says.