Police in Zimbabwe have used batons, tear gas and water cannon to beat up and disperse supporters of the main opposition party in the capital, Harare.
They were due to hear a speech by Nelson Chamisa, the leader of the Movement for Democratic Change (MDC).
The latest police action comes as the opposition accuses President Emmerson Mnangagwa of adopting the same heavy-handed tactics used by his predecessor, Robert Mugabe.
On Sunday, Mnangagwa defended his record, saying his administration was opening up political and media space.
Police have banned several MDC gatherings.
Correspondents say the government appears determined to prevent the opposition gaining political capital from the deepening economic crisis.