A bomb exploded inside a restaurant in Beni, a city in the east of Democratic Republic of Congo, the mayor said on local radio.
It was not immediately clear whether there were any casualties. Reuters could not immediately reach officials for comment.
"There is a bomb that just exploded in the city centre," Beni's mayor Narcisse Muteba Kashale said. "For safety, I'm asking the population to stay home."
A Reuters journalist nearby said he heard an explosion around 19:00, just after the afternoon Catholic mass, near the city's main road, followed by gunshots.
Images shared on social media showed dozens of green chairs scattered across a road, some melted or shouldering. Three bodies could be seen among the wreckage. Reuters could not immediately verify the authenticity of the images.
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