The Football Association is investigating a banner displayed by Crystal Palace fans during Sunday’s 1-1 draw with Nottingham Forest at Selhurst Park.

The banner showed Forest owner Evangelos Marinakis pointing a gun at midfielder Morgan Gibbs-White, alongside text denying allegations of blackmail, match-fixing, drug trafficking and corruption. Marinakis has denied any wrongdoing.

Forest sources said the club was disappointed the banner was allowed into the ground. Palace have been approached for comment.

The FA will decide whether Palace face punishment. Its rules prohibit offensive or defamatory material on banners.

The incident follows a summer dispute between the clubs after Palace were removed from the Europa League under Uefa’s multi-club ownership rules, with Forest taking their place. Palace chairman Steve Parish called the ruling “the biggest injustice in the history of football”.

Forest consider the banner inflammatory and xenophobic and are questioning why Palace’s ownership has not condemned it.

Gibbs-White, who was linked with Tottenham earlier this summer, recently signed a new deal at Forest in an interview alongside Marinakis.