The 22-year-old shot-stopper is thought to have been caught on Brentford`s official match video gesticulating at the Bees forward during last Saturday`s game at Griffin Park.
If the video footage confirms the charge, the Northern Ireland keeper could face criminal action as well as punishment from the Football League.
"We are taking this allegation extremely seriously," Police Inspector Dave Page said. "If the incident is as bad as it sounds, then we will definitely be taking further action."
