Burundi sentenced 21 activists from a key opposition party to life in jail for "armed revolt" on Friday after a jogging protest earlier this month turned into violent clashes with police, a rights campaigner said.
A further 26 were given terms of between two and 10 years for their role in protests in the capital Bujumbura on March 8, which snowballed into the worst violence since the end of the civil war 12 years ago.
The campaigners from the Movement for Solidarity and Development (MSD) were sentenced for "taking part in an armed revolt, rebellion and contempt of the security forces," said Pierre-Claver Mbonimpa, who heads Aprodeh, an association that campaigns for the rights of prisoners.
The remaining 22 accused were acquitted, he said.
Some 20 activists and five police officers were wounded -- some from bullet wounds -- when a "group jog" by members of the MSD turned into violent clashes with police.
MSD head Alexis Sinduhije, a former journalist, has been on the run from police since the clashes. He too faces life in prison if caught.
Francois Nyamoya, the MSD's secretary general, called the legal proceedings against campaigners "a judicial farce".
The authorities have since restricted group marching or jogging in the street, claiming opposition groups are using them as an excuse for "uprisings".
Burundi is growing increasingly tense in the run-up to presidential elections in 2015.
That has been made worse in recent weeks after the main Tutsi party, Uprona, withdrew from the Hutu-dominated government.