Scotland international Leigh Griffith faces disciplinary action after allegedly sending a racist message on Twitter.
The 22-year-old striker lashed out at user Zak Iqbal on the social network, telling him: "Go back to your own country."
Griffiths is on loan at Hibs from Championship club Wolverhampton Wanderers. The club said it was "angry and disappointed" by his actions.
Griffiths admitted it was wrong and immediately placed his Tweets behind security, so that only his 13,000 followers can read them.
Now officers from Lothian and Borders Police are carrying out enquiries into the incident.
Griffths claimed his "out of order" words were sparked after he was sent "provocative" comments on the website. He said his response had been "unacceptable."
This race row will be an unwelcome distraction at Molineux. The club recently appointed Dean Saunders to lift it from the doldrums after a run of four straight defeats and only three wins in 15 games.
Griffiths has hit 14 goals during his loan spell at Hibernian and is likely to remain at the East Road Stadium all season.
A Wolves spokesman said: "Wolves are aware of an alleged racist comment made on Twitter last night by Leigh Griffiths.
"The club condemns such comments in the strongest possible terms and are extremely angry and disappointed.
"The player is currently on loan at Hibernian FC and is likely to remain there for the rest of the season.
"He is, therefore, subject to the disciplinary procedures of Hibernian FC and those of the Scottish Football Association.
"However, Wolves are in dialogue with Hibernian and are making their feelings known on the matter."