Mick Everett, Charlton FC's Head of Operations, said:
"The club was shocked to hear of the rowdy, intimidating behaviour, and the chanting of racist songs on a train by a handful of our supporters.
"Their actions are totally condemned by everyone at the club and indeed, I am sure, by Charlton supporters everywhere.
"Although this isolated incident does not reflect on the overwhelming majority of our fans, these arrests are a kick in the teeth to everyone associated with the club, who have put so much effort into our campaign over the years.
"The club will now look to impose additional appropriate sanctions on those involved."
More top news
Patricia Al from ran up the monster debt after using her O2 mobile in Turkey.
The position, posted on the British Monarchy website, pays £16,000 a year for 20 hours a week.
Police are hunting for a passenger seen on CCTV after a 15-year-old boy was attacked and left with a punctured lung.