ATo in BB, 6-max 1/2

[PMR]

After 100 hands, UTG is 24.1/15.0/3.3 and MP is 85.2/5.6/0.7. CO is also very loose preflop.

Full Tilt 1/2 Hold'em (6 handed) Hand Converter

Preflop: Hero is BB with T[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/club.gif[/img].
<font color="#CC3333">UTG raises</font>, MP calls, CO calls, <font color="#666666">2 folds</font>, Hero calls.

Flop: (8.50 SB) A[img]/images/graemlins/heart.gif[/img], 6[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">Hero bets</font>, UTG calls, MP folds, CO calls.

Turn: (5.75 BB) 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">UTG raises</font>, CO folds, Hero calls.

River: (9.75 BB) J[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero</font>...?

Final Pot: 13.75 BB

UTG's raise on the turn has me worrying about K[img]/images/graemlins/heart.gif[/img], so I'm not sure how to play the river. Check/call, bet/call, bet/raise? Any input is appreciated.