Brighton have apologised for “any offence caused in China” by a post on social media that featured an image of a Japanese World War Two soldier.
The post from the club’s academy featured Japan international Kaoru Mitoma and a youth player posing with a football card featuring Hiroo Onoda.
Lieutenant Onoda was the last Japanese soldier to formally surrender, 29 years after the country’s defeat in the war.
Brighton’s post was controversial in China as Japan committed atrocities in the country during the war.
There has been some backlash from fans expressing anger and disappointment on Chinese social media platform Weibo.
Onoda held out in the Philippine jungle for 29 years before surrendering, because he did not believe the war had ended. He received a hero’s welcome on his return to Japan.
The Philippine government granted him a pardon, despite killing 30 people on the island of Lubang that he mistook for the enemy.
“The club sincerely apologises for any offence caused in China by a recent post about our academy’s participation in the Premier League Christmas Truce Tournament,” the club’s academy said in a post on X.
“We hugely value our fans in China and had no intention of causing any offence.”
Alongside the image, the post said the club’s under-12s boys team had won the Premier League Education Project and would be going to Belgium to play in the Christmas Truce Cup.
The Premier League said the tournament “offers academy U12 players a chance to test their footballing talent against top European Clubs while gaining an understanding of the historical events that shaped our world”.
The tournament is named after the series of spontaneous ceasefires that occurred around Christmas in 1914 between British and German soldiers during World War One, with football matches being played in several locations.
BBC Sport has been told by Brighton officials it was a genuine error and the controversy was not known to the club or the Premier League.
It is understood the league – who co-judged the winners of the Education Project – were not aware of the specific people involved in the work.