The report says Police were called to a house in the early hours of Friday morning following a report of assault. They then arrested the 26-year-old and took him away from questioning before being released on bail.
A spokesman fro 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."
Niasse only joined Everton in January for £13.5million in January from Russian side Lokomotiv Moscow.
The Senegal international has struggled for form and fitness since moving to Goodison, with a wrist injury delaying his debut until end of February.
He has made just six substitute appearances since then, scoring no goals, with his only start coming against Leicester earlier this month.