Hundreds of opposition supporters marched in the Angolan capital Luanda on Saturday to protest against poll law amendments they say will undermine general elections next year.
President Joao Lourenco this week implemented a bill to centralise vote counting rather than tally them at each municipality and province - a move critics fear will reduce transparency.
All opposition MPs either abstained or voted against the reform, but had little sway in a parliament dominated by the ruling People's Movement for the Liberation of Angola (MPLA).
The main opposition party UNITA - the National Union for the Total Independence of Angola - organised Saturday's march to demand "free and fair elections".
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UNITA has suggested measures to avoid alleged fraud, including biometric voter identification and involving civil society in ballot counting.
Hundreds of protesters marched into the city centre, holding signs that read: "Let's demand our rights" and "We want biometric control".
Police armed with batons manned the demonstration.
Elected in 2017 after his predecessor retired from a 38-year reign, Lourenco is expected to run for a second term in 2022 presidential, parliamentary and local elections.
The MPLA has ruled the southwest African country since independence from Portugal in 1975.
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