Meta-owned photo-sharing platform Instagram has reportedly blocked posts using a hashtag in memory of the victims of a Ukrainian airliner shot down by Iranian security forces two years ago.
According to the BBC, families of the 176 victims found posts with the hashtag #IWillLightACandletoo, as well as its Persian version, were not visible to users.
A cybersecurity expert said it appeared that Iran had orchestrated the block by reporting the posts.
The social media giant said the hashtag was "restricted by mistake", the BBC report said.
The Ukraine passenger flight crashed on January 8, 2020, by Iranian missiles shortly after it took off from Tehran, killing all 176 people on board.
Iran said that its forces "accidentally" shot down the plane.
Ukraine has rejected the findings of an Iranian investigation into the crash as a "cynical attempt" to conceal the truth.