Police were called to a property in the early hours on Friday morning and arrested the 26-year-old Senegalese striker.
A spokesman for Greater Manchester Police said: “At 12.55am on Friday 13 May 2016, police in Salford were called to an address following a report of an assault. Officers attended and a 26-year-old man was arrested on suspicion of assault and was taken into police custody for questioning. He has been bailed until 27 May 2016 pending further enquiries.”
A spokesperson for Everton said: “The Club condemns unreservedly any form of abuse. In this case, we understand an investigation is underway to establish the facts.”