A person with knowledge of the situation told The Associated Press that Higgins reported threats on his home phone, which has an unlisted number, and on the office phone for his roofing company. The person requested anonymity because the investigation is ongoing.
The Facebook page for Higgins' roofing company also was inundated with negative comments about Higgins and the quality of his company's work.
In a statement Wednesday, the Kentucky athletic department says it encourages fans to demonstrate good sportsmanship and discourages other kinds of behavior.