Millwall have followed up the FA's launch of an investigation into alleged racist chanting during the clubs FA Cup victory over Everton, with a statement that any fans found guilty will face a lifetime ban.
Millwall's dramatic 3-2 win was marred by crowd trouble outside the ground and videos have now emerged which appear to show some home fans singing racist chants during the match.
A club statement was unequivocal in its summation as to the consequences for those found guilty.
"Millwall Football Club is aware of, and extremely disappointed by, a video circulating online displaying alleged racist chanting during Saturday's victory over Everton.
"The club will, as is commonplace following such incidents, work with all relevant authorities during investigations into the matter and look to identify individuals involved. Anyone identified and guilty of such abuse will be banned from The Den for life."
In addition, a spokesperson for the FA said the governing body was aware of the incident and was investigating.
Anti-discrimination group Kick It Out condemned the chants and called for action to be taken.
"The racist chanting heard from some Millwall supporters during yesterday's match is disgusting and typical of mass discriminatory chants that continue to go unpunished," a statement said.
"We reiterate our message: racial hatred - and all forms of discrimination - have no place in society, especially not in 2019. There is no reason why a footballing environment should be the exception to this rule.
"Kick It Out wants to see the relevant authorities take swift, firm and decisive action against the perpetrators."
Prior to the match at The Den, a man suffered a slash wound to the face during clashes in Southwark, with the Metropolitan Police saying they believed the fight was between Millwall and Everton fans.
Video posted on social media shows police attempting to separate two large groups as punches were thrown.