Security forces clashed with the Rwenzururu royal guards, with more than 60 people killed.
The opposition leader says that young Ugandans must continue their defiance of the Museveni regime.
Yoweri Museveni has vowed to rid the East African country of corruption.
Eight top Ugandan police chiefs are accused of brutalizing Kizza Besigye's supporters.
The Ugandan president also recently promoted his son to one of the military's highest ranks.
Supporters of the imprisoned opposition leader staged a protest at the court.
Besigye is being held in Uganda's only maximum security prison.
Muhoozi Kainerugaba trained at Sandhurst and has made a quick ascent through the army's ranks.
Kizza Besigye has been under house arrest since February 18 elections.
The Forum for Democratic Change has been demonstrating against Museveni's controversial victory.
The police have denied they were involved and accused Mbabazi of "dirty tricks."
President Yoweri Museveni was re-elected in a controversial presidential election in February.
The international community responded in a variety of ways to Museveni's re-election.
President Yoweri Museveni won Thursday's controversial elections with 61 percent of the vote.
Despite the blackout, #UgandaDecides is still trending.
President Museveni said anyone trying to stir up violence ahead of the polls would be dealt with harshly.
Besigye, Uganda's main opposition presidential candidate, was briefly detained on Monday.
Besigye is the main challenger to Yoweri Museveni in Thursday's elections.
Amama Mbabazi has pledged to return Amin's remains to Uganda if he is elected.
Museveni is seeking re-election on February 18 after 30 years in power.