A false report of an explosion at the Pentagon, accompanied by an apparently AI-generated image, spread on Twitter on Monday morning, sparking a brief dip in the stock market.

"There is NO explosion or incident taking place at or near the Pentagon reservation, and there is no immediate danger or hazards to the public," the Department of Defense's Pentagon Force Protection Agency and the Arlington County fire department said in a joint statement on Twitter.

The fake image circulating on Twitter showed a black cloud of smoke near a building. The accounts posting it claimed it depicted the Pentagon.

But the image was likely generated by artificial intelligence, experts said, in an example of potential for misuse of the increasingly popular and prevalent technology that they have been worried about.

"Check out the frontage of the building, and the way the fence melds into the crowd barriers. There's also no other images, videos or people posting as first hand witnesses," Nick Waters of the open-source investigations group Bellingcat wrote on Twitter.

Soon, other apparently fake AI images purporting to show an explosion at the White House popped up.

Major stock market indices briefly dipped on the false reports before recovering.

Many of the Twitter accounts that spread the hoax carried blue checks, which used to signify that the social network had verified the account is who or what it claims to be. But under new owner Elon Musk, the company now gives a blue check to any account that pays for a monthly Twitter Blue subscription.

Among the blue-check accounts that shared the false Pentagon image were an one impersonating Bloomberg News and the real account of the Kremlin-linked Russian news service RT.

RT later deleted its post. The fake Bloomberg account has been suspended by Twitter.

Twitter responded to a request for comment with an auto-reply containing a poop emoji.

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