Police investigating online racist abuse directed at Wales internationals Ben Cabango and Rabbi Matondo have arrested a man in his 20s.
Metropolitan Police have been investigating the abusive messages.
"One man, aged in his 20s, was arrested on Friday, 31 December 2021 and released under investigation," a spokesperson said.
"Enquiries remain ongoing."
Matondo, 21, used his Twitter page to highlight the abuse last March, and was critical of Instagram for "doing absolutely nothing" to combat racism.
Facebook, which owns Instagram, then issued a statement saying they had "removed the accounts that sent messages" to Matondo, who is on loan at Cercle Brugge from Schalke 04, and Swansea City centre-back Cabango.
South Wales Police said at the time they were "investigating the origin of racially motivated social media posts".
The Football Association of Wales said it was "disgusted by the racial abuse" and was working with police "to ensure this kind of abhorrent behaviour is reported and investigated".
Wales beat Mexico 1-0 thanks to a Kieffer Moore goal.