The Fishin' Company, one of the largest suppliers of frozen fish to Walmart and other major US retailers, has lost three of its top executives in the past six months, while at the same time undergoing a massive, unexplained hiring spree.

President Ryan Grace, Chief Operating Officer Heath England and Chief Financial Officer Kevin Wisel have all left the Pennsylvania-based company within the past six months.

Grace, who departed in April, had been with the group since 2009, and served as president since 2016.