The Terriers head coach spoke out after the 2-1 defeat at home to Brighton & Hove Albion was marred by unsavoury chants from a section of the home support.
It came on Saturday as the Yorkshire club, who have pledged to ban any of those involved, supported the start of the rainbow laces campaign, which is a show of support for the LBGT community.
“I hadn’t heard it during the game but I am aware of the reports,” said Wagner. “We will be very strong with it and make sure no-one is welcome who has said this. We will deal with it very strongly.”
Huddersfield pledged to investigate the chants, which were aimed at the visiting supporters.
Asked if he had a message for those involved, Wagner replied: “Stay at home and get your head clear. I have no clue what they think and what their idea is.
“I am totally clear and happy that my club is strong in it’s mindset as well. These people are not welcome.”