The United Nations (UN) Human Rights Chief on Friday called on the government of the Democratic Republic of Congo (DRC) to halt violence and inflammatory speech ahead of the country’s long-delayed December 23 presidential election.

Michelle Bachelet‘s comments came a day after a fire at a warehouse in the capital of Kinshasa destroyed thousands of voting machines and ballot boxes meant for a vote that could mark Congo’s first peaceful transfer of power.

Candidates for President Joseph Kabila‘s ruling coalition and the opposition blamed each other for the incident. Violence has flared on the campaign trail this week, with security forces killing at least two people at opposition gatherings.

“In an already tense electoral environment, I urge the government to send a clear signal that threats and violence against political opponents will not be tolerated. I am deeply worried about the reports of excessive use of force, including live ammunition, by security forces against opposition rallies,” says Bachelet.

Congo’s forensic police are investigating Thursday’s blaze and the national electoral commission said the vote would go ahead as scheduled.

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