Riot police used tear gas to break up opposition supporters who had planned to march through Mali’s capital Bamako on Saturday, calling for transparency in next month’s presidential election, witnesses and the authorities said.

President Ibrahim Boubacar Keita plans to run for re-election in the July 29 polls, despite criticism that he has not done enough to cut youth unemployment or end an Islamist insurgency and tit-for-tat ethnic killing in the north.

The authorities had banned Saturday’s march in Bamako, organized by a coalition of political parties opposing Keita.