(AP) -- Researchers tracking the massive oil spill in the Gulf of Mexico say computer models show the black ooze may have already entered a major current flowing toward the Florida Keys, and are sending out a research vessel to learn more.

William Hogarth, dean of the University of South Florida's College of Marine Science, told The Associated Press Sunday that one model shows that the oil has already the loop current, which is the largest in the Gulf. The model is based on , ocean current and spill data from the U.S. Navy and the National Oceanic and Atmospheric Administration, among other sources.

Hogarth said a second model shows the oil is 3 miles from the current - still dangerously close.

The current flows in a looping pattern in the Gulf, through the area where the blown-out well is, east to the Florida Keys National Marine Sanctuary.