Is Uganda's Museveni following in Mugabe's footsteps?
They are particularly alarmed by the arrest this month of Kizza Besigye, seen as the man likely to pose the strongest challenge to Mr Museveni in elections due early next year.
Some analysts say the involvement of the military in Dr Besigye's case is a sign of the growing influence of the army in various aspects of Ugandan life.
The authorities accuse Dr Besigye of contacting rebel groups in order to topple Mr Museveni and they say they have the evidence to back up the charges.
Photo (AP/BBC) Dr Besigye (in blue cap) who returned from four years in exile last month was charged with treason - and rape - in the High Court but a judge has agreed to grant him bail.
However, he has also been charged in a military court with terrorism and unlawful possession of weapons and he remains in custody.
Dr Besigye's arrest led to two days of riots in Kampala - see BBC In pictures: Kampala riots. Anti-riot police and soldiers fired tear gas and bullets against protesters in the central streets of Kampala. Riot police battled opposition supporters for two days, after the arrest of their leader Kizza Besigye.
A suspected looter was shot dead in this street. There are growing concerns over the political climate in Uganda. Human Rights Watch has urged a fair trial for Dr Besigye.
Many Ugandans are unhappy at the military's involvement in the Besigye case.