A report in the Guardian claims Torben Aakjaer published anti-immigration posts on the social media website.
Those alleged posts now appear to have been removed.
United suspended Aakjaer after the allegations came to light and after a brief investigation, they sacked the Dane.
"We have terminated our association with him (Aakjaer)," a United spokesman said on Wednesday night.
Responding to the initial claims, United issued a statement which ended: "Manchester United is an inclusive organisation and will not tolerate this sort of behaviour."
Aakjaer, who has previously worked at Hamburg, started scouting for United in 2011.
On his Instagram page, the Dane has posted several pictures of the club's training ground in Carrington which he described as his "working place".
Aakjaer posted a selfie with United winger Nani and he also published a picture of a letter he received from Sir Alex Ferguson wishing him well on his wedding day.
Source : PA