Kagame's ex-comrades in arms call for his overthrow

Nothing was stolen during the attack and Kigali denied any involvement. But Pretoria said security operatives from an unnamed African country were involved.

Power is increasingly centered around Kagame alone, rather than in the hands of a united RPF and the president is increasingly "isolated within the army", Guichaoua said.

"The so-called 'dissensions in the inner circle' can also be seen as the consequence of the widening of the ruling group," an RPF member told AFP.

"Those who grew disgruntled are people who failed to adapt to change i.e. the widening of the RPF membership ... a lesser role for the security organs and the emergence of a new generation," he said.

"This is not a trend that should be seen only as a narrowing or a regression."

Karegeya and Kayumba are privy to the regime's darkest secrets. Their margin for manoeuvre on the international scene is limited by war crimes allegations against them but the two represent a serious challenge to Kagame, in particular if they can obtain outside support.

Kagame also downplays the importance of those who flee the country.

"I think there are more crises in the minds of outsiders about the RPF than there are within the RPF", he said last month.