The Microsoft-owned search engine Bing is not displaying any image results for “tank man,” the most iconic image of the Tiananmen Square Massacre, even when the term is searched from within the United States. Microsoft claims the phenomenon is due to an “accidental human error,” and that the company is “working to resolve this.”

“There are no results for tank man,” reads a message from Bing website reads after searching for the term.

“Check your spelling or try different keywords,” the website further advises.

“Tank Man” refers to the iconic image of an unknown, lone protester carrying a pair of plastic shopping bags, standing in front of a row of Chinese tanks during the communist regime’s violent crackdown on protests in Tiananmen Square in 1989.

The photo of “tank man” — which has since become a symbol of resistance against tyranny — was taken on June 5, 1989, which suggests the apparent censorship of the image arrives on its 32-year anniversary of the Tiananmen Square Massacre.

The famous image is also censored on Yahoo and DuckDuckGo — both of which use the Bing search engine. Meanwhile, the image is not censored in the U.S. on Google. The censorship was first reported by Vice’s Motherboard.

While China already censors content involving tank man — and talk of the Tiananmen Square Massacre in general — the image being censored in the United States is a new development.

Shane Huntley from Google’s Threat Analysis Group first tweeted a screenshot of the Bing search result lacking images of tank man, asking Microsoft president Brad Smith to explain.

“Same in UK,” tweeted security researcher Kevin Beaumont, who also shared an image of the failed image results for tank man.

Social media users also expressed that they are unable to find image of tank man on Bing in France, Switzerland, and other countries.

A Microsoft spokesperson told Motherboard in an email that the censorship is “due to an accidental human error and we are actively working to resolve this.”

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