According to the article, Metliss, who is the chairman of the Action Against Discrimination charity, took pictures of the alleged perpetrators and reported the incident to nearby stewards before being moved to the family enclosure "for his own safety".

Chelsea last week launched a 'Say No to Antisemitism' campaign as part of their own inclusion work through the Building Bridges initiative.

Club owner Roman Abramovich was joined by high-profile individuals from across the Jewish community and by antisemitism campaigners at a gathering ahead of the January 31 match against Bournemouth, which saw the lighting of a candle by Holocaust survivor Harry Spiro.

Following the emergence of allegations at Vicarage Road, Chelsea issued a strongly worded statement on Tuesday evening and have launched an investigation in co-operation with Watford and the police.

"Antisemitism has no place in our club, football or wider society," a Chelsea spokesman said.

"Anyone found guilty of antisemitic language or behaviour will face action from the club, including bans, and will be asked to attend equality education courses.

"We welcome the fact that Chelsea fans have reported this behaviour, which shames our club.

"We ask all fans who share our vision for a game open to all to report any kind of discrimination they witness or experience.

"We will be working closely with the police and Watford to identify those responsible and will take the appropriate action."