That kinda looks like a snakehead. I watched it on river monsters the other night. Very aggressive fish and will eat everything. There a invanion species to your waters. I could be wrong but take pictures to your local wildlife office and they could tell you.
Yep, that's a freshwater eel. The eel is very slimy and slick with skin like catfish. They make great cut bait.
The snake head has scales I believe and very big teeth.
Fresh water eels get very large. My dad used to catch eels up as long as he was (5'10" and I've seen them longer) on the AL/Tombigbee rivers on trotlines and in boxes. We'd cut them up and use them for more bait.
Funny things about those fish are that you'll be fishing and hear a Psst type sound, from them blowing or taking a breath on top of the water. it'll scare the turd out of ya, if you aint payin attention...lol