A man has been arrested on suspicion of sending racist tweets to Northampton players Adebayo Akinfenwa and Clarke Carlisle, chairman of the Professional Footballers' Association.
Insp Phil Kings of Northamptonshire Police said a man was held on suspicion of a racially aggravated offence.
The incident is jointly being investigated by Gloucestershire and Northamptonshire Police.
A Northampton Town spokesman said: "We became aware of some tweets that had been sent to our players on Wednesday evening and we immediately notified the police.
"As this is a live investigation it would be inappropriate for us to comment further."