This was the Kentucky River, correct? If so, I'll bet those were gar. They spawn this time of year, or maybe a little later in the summer. If you want to get into a tussle, rig up a rope lure http://www.garmanjack.net/hookless.html cast it out and hang on. If they are gar and you don't want to fool with them (and who could blame you?), you'll probably want to go somewhere else for a while.