The Met Police say a man has been held on suspicion of a public order offence and taken into custody.
A man has been arrested during the FA Cup final at Wembley after concerns about a football shirt slogan.
A photo of the back of a man wearing the number 97 and the words “not enough” on a white shirt was shared widely on Twitter.
Some Twitter users said it referred to the Hillsborough Disaster when 97 Liverpool fans died as a result of a crush in 1989 at Hillsborough Stadium.
Police said a man had been arrested on suspicion of a public order offence.
The Metropolitan Police tweeted that he had been taken into custody.
The force confirmed to the BBC that the arrest was solely due to the shirt worn by the football fan but would not confirm that it was because of its alleged reference to the disaster.
Sharing a tweet by a Liverpool FC fan account called the Kop Watch, the Met’s events Twitter account said: “We are aware of this and have worked proactively with officials at @wembleystadium to identify the individual.
“He has been arrested on suspicion of a public order offence and taken into custody.”
The force tweeted at the end of the match, which Manchester City won 2-1 against Manchester United.
Officers also said they were investigating after an object was thrown towards the pitch during the first half of the game.
The Met tweeted that it was working with stadium officials and reviewing CCTV footage.
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