The 29-year-old forward, who helped England to a series win over New Zealand on Saturday, joined the Giants from Castleford in July 2012.
Injury limited him to just 13 Super League appearances last season.
The Giants confirmed in a statement that they would not be making any further comment at this stage.
Huddersfield Giants have suspended England international Brett Ferres "pending an internal investigation into conduct away from the club".