Bolsonaro supporters clash with police before major rally in Brasília

Violence erupts as rightwing activists attempt to break through blockade and force their way to congress

Pre-dawn skirmishes have erupted between police and supporters of Brazil's president, Jair Bolsonaro, as rightwing activists tried to force their way towards congress before major pro-government rallies that have put Latin America's biggest democracy on edge.

Footage published by the Brasilia-based news website Metropoles showed military police using pepper spray to repel a crowd of cheering Bolsonaristas in the early hours of Tuesday.