The Premier League champions' weekly email featured a logo similar to that used by the Nazis, and the club's head of media has since labeled its use “completely inappropriate”
The image was used in the weekly United Uncovered email, and also featured the headline 'New Order' – a term intended to describe the Red Devils' crop of young players, such as Adnan Januzaj and David de Gea, but which is closely tied to Nazism.
United's head of media, David Sternberg, has since apologized for the graphic on Twitter and revealed that the club will launch an investigation into why the image was cleared for publication.
"The creative is completely inappropriate; we apologise unreservedly and are taking appropriate international action," Sternberg tweeted.
Supporters then contacted Sternberg demanding to know why the image has been allowed to go to publication without being vetted, to which he replied: "That's what is being investigated – obviously it shouldn't have."
The Premier League champions won their last outing against Stoke City, as quick-fire goals from Wayne Rooney and Chicharito saw them come from behind to beat the Potters 3-2.