The Watford side were playing Italian team Latina Calcio in a Wojtyla Cup game in Rome on Wednesday when they were taken off by coach Dave Hughes following an incident.
The club and Kick It Out are both now trying to find out the full facts behind the incident - a video of which has appeared online.
A Kick It Out spokesman said: "We have been made aware of an incident, we have been in touch with the club and they and we are now looking into exactly what happened."
Source: PA
Source: PA