An artist was stopped outside Buckingham Gate in central London by police officers on Wednesday afternoon because they believed the artwork he was carrying was a rifle.
Artist Ray Fiasco said he had simply been walking through the area carrying his artwork.
The police told BuzzFeed News they had received a report of someone holding a "suspicious-looking package".
Fiasco said the armed police pointed guns at him and searched his belongings.
The police have denied Fiasco's claims that he was searched or that they pointed their weapons at him.
In a statement provided to BuzzFeed News, the Metropolitan police said that at no stage did officers point their weapons at Fiasco.
The Met stated that he was spoken to by officers, but that he was not searched or arrested.
The police told BuzzFeed News that officers conducted a "low-key stop" on Fiasco, who matched the description they were provided.
Fiasco said he asked the police what the description was and was told by an officer: "tall, black, and wearing a jacket".
He added that even after police realised his "rifle" was in fact an artwork, they said they still "needed to check CCTV".
Fiasco tweeted about how he had to "crack jokes" and show them he was "a British lad at heart", despite being targeted by "an army".
He said he feared that if he didn't remain calm, he could end up like Jean Charles de Menezes, the unarmed man who was shot dead by police in 2005 after being misidentified as a terrorist suspect.
Fiasco said he was grateful that there were tourists around him when the incident occurred, because he could have ended up "a memory".
Rossalyn Warren is a senior reporter for BuzzFeed News and is based in London.
Contact Rossalyn Warren at firstname.lastname@example.org.
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