The incident appeared to happen while former World Champion Stephen Hendry was being interviewed during a break in play during the tournament.
The BBC has a studio in the Winter Garden, where onlookers can watch all the interviews taking place. It is not known if the people were related.
The man appeared to whisper in the child’s ear before proceeding to nibble on his ear with viewers left shocked.
The boy did appear upset as he noticed he could be seen on the live broadcast and then smiled and waved towards the camera as the man pulled back.
South Yorkshire Police said: ‘Yesterday, Thursday 25 April at 9.20pm, we received a call to inform us of a video circulating on social media of a man and a boy at the Crucible in Sheffield.
‘We are aware of the footage and officers will be reviewing the content.’
A spokesperson for the World Snooker Tour said on Friday: ‘we are aware of this incident and it is now a police matter’.
One fan quickly posted the a clip of the incident on social media, writing ‘what the f*** did I just see?!’ with the ‘sick’ emoji.
Over 10 million people have watched the video, with many expressing concern.
