Anglers hooked into at least a few of the big, ugly fish near the Xcel Energy power plant in recent days.
Discovery marks first time jumping carp species has been detected on upper Mississippi.
A new scientific study contradicts a 2012 report that invasive fish DNA had been found in the river.
Federal legislation would organize anti-carp effort, and new research is looking at ways of stopping the invasive fish.
The U.S. Fish & Wildlife Service would be put in charge of a multi-agency effort to slow the spread of invasive carp in the Mississippi River and rivers which flow into it like the St. Croix.
New efforts are underway to protect the St. Croix River from the invasive carp, including an opportunity for individuals to take action.
Steve Johnson explains what the lower St. Croix River region has to lose if Asian carp impact the recreational boating industry.