Arsenal have condemned a fan on controversial supporters channel AFTV for a racist slur made against Tottenham's Son Heung-min.
Claude Callegeri was heard saying "DVD's going off" as Son was substituted during Spurs' 2-1 north London derby win on Sunday and received widespread criticism. DVD is a well-known racist slur against Asian people.
Callegeri has since been removed from the channel "indefinitely" and apologised, but only after he and channel owner Robbie Lyle attempted to justify the remark.
The Gunners have distanced themselves from AFTV, which has over 1million subscribers, and condemned the "unacceptable racist behaviour".
"We are aware of a video on social media in which an Arsenal supporter uses a racist slur towards Tottenham Hotspur's Son Heung-min during Sunday's match," they said in a statement.
"We operate a zero-tolerance approach to any form of discrimination and we unreservedly condemn this unacceptable racist behaviour.
"Our records show that the individual involved is not an Arsenal season-ticket holder and does not hold any form of ticket membership.
"The platform in question has no official association with Arsenal."
Lyle and Callegeri had appeared in a video on Tuesday to address the issue, suggesting he meant that Spurs would release a celebratory DVD of their derby win.
Lyle later performed a u-turn and stood down the outspoken Callegeri from the channel.
He tweeted: "I would like to sincerely apologise for the derogatory remark heard on the AFTV livestream on Sunday, and for the response video that we put out today where we failed to apologise and take onus for the comment," Lyle said on Twitter.
"As a channel that has millions of viewers around the world, I fully recognise the power that comments made by myself or people on our platform have, and it is paramount that we do not allow comments of this nature to be made in any form.
"As such, it is only appropriate that Claude is removed from the channel indefinitely.
"In no way do I or AFTV condone racism of any kind and it is important we take appropriate action in line with the comment made."
Callegeri also apologised for his actions in a video on Twitter.
"Unfortunately, what's happened here is a few days ago in the game against Spurs, I made a comment, my only thing was the timing was all wrong when I made the comment.
"It's caused a lot of offence to Son and all the Spurs fans, and I want to apologise to Spurs fans and Son for that because of the offence it has caused.
"What can I do? It's caused a lot of offence and I want to apologise because I admire Son as a player."