British Transport Police have confirmed officers interrupted alleged anti-Semitic chanting on a train following Chelsea's match at Brighton on Sunday.
The incident comes after the alleged racial abuse of Manchester City's Raheem Sterling on December 8, which prompted Chelsea to suspend four supporters, and the anti-Semitic chanting at last Thursday's Europa League tie with Vidi in Budapest.
"Officers received reports of anti-Semitic chanting on board a train from Falmer to Brighton at around 4pm (on Sunday)," the BTP statement read.
"BTP attended and three men were spoken to by officers, but at this time no one has come forward to make a complaint."
Chelsea last Thursday condemned the discriminatory behaviour of a minority of supporters and vowed to take the strongest possible action against perpetrators.
Chelsea in January approached Barnardo's, the children's charity, to commission an independent review into historic allegations of racism at the club.
And the Metropolitan Police on Tuesday confirmed they received an allegation of historic "racially-aggravated assault" earlier in September.
A Met statement read: "Police received an allegation of non-recent racially-aggravated assault in September 2018. Enquiries are ongoing.
"There have been no arrests. We do not confirm who we have spoken to as part of an investigation."
A Chelsea spokesman said: "We take allegations of this nature extremely seriously and they will be fully investigated.
"We are absolutely determined to do the right thing, to assist the authorities and any investigations they may carry out, and to fully support those affected, which would include counselling for any former player that may need it."
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