The vigil was held in the Saint Sarkis Cathedral in Tehran on April 24. Between 600,000 and 1.5 million Armenians are said to have been killed in systematic decimations by Ottoman Turkey starting in 1915.
Turkey denies the claim, saying the killing of the Armenians was not a genocide and the fatalities were victims of war.
Below find a selection of photos form the memorial congregation at the Saint Sarkis Cathedral in Tehran:
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