Thames Valley Police are investigating a report of alleged indecent exposure that occurred during Newcastle’s FA Cup win at Oxford United on Tuesday night.
A supporter allegedly exposed himself after Allan Saint-Maximin's extra-time winner at the Kassam Stadium that saw Newcastle beat League One Oxford 3-2 in their fourth-round replay.
Thames Valley Police have confirmed they are now looking into the incident but no arrests have been made so far.
A Newcastle spokesperson said: "We are aware of footage showing the clearly inappropriate actions of a supporter during the closing stages of Tuesday night's FA Cup fourth-round replay at Oxford United.
"We have been asked to assist the police in their efforts to identify the supporter in question and we will provide our full support."
Newcastle face Championship leaders West Brom in the fifth round of the FA Cup at The Hawthorns on March 3.