Two people were pictured holding up a phone showing the six-year-old Bradley Lowery's face as they laughed following the club's 3-0 Championship defeat to Sunderland.

Bradley was a mascot for England and Sunderland and struck up a close friendship with striker Jermain Defoe, who called him his "best mate".

Read more: Police contact family of Bradley Lowery after fans appear to mock him

He suffered from rare childhood cancer neuroblastoma, which was diagnosed when he was 18 months old.

Sheffield Wednesday said they had launched an investigation with South Yorkshire Police.

In a post on X, formerly Twitter, the club wrote: "We roundly condemn this outrageous and utterly deplorable behaviour. We can only apologise for the undoubted distress caused to Bradley's family and friends."

South Yorkshire Police confirmed they were investigating "public order offences" in a post on X directly under a picture widely circulated of the two fans. They were working with the club on identifying the men and appealed for anyone with information to get in touch.

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The Bradley Lowery Foundation, a charity set up by Bradley's mother, shared the photos on Facebook, saying they were "so sad for me to see".

"Whatever happened to 'cancer has no colours' let alone respect for a family that lost their baby to cancer."

The Sheffield Wednesday FC Women's Supporters Group launched a fundraiser for the charity in response to the photos.

"We won't let the abhorrent actions of a few define our club," they wrote on X.