River advice needed

Villan is 70/30/2. The river bet was an attempt to block. Alternatives (any street)? check-fold river?

Party Poker No-Limit Hold'em, $ BB (6 max, 6 handed) FTR converter on zerodivide.cx

UTG ($16.49)
Hero ($33)
CO ($7.15)
Button ($30.05)
SB ($3.27)
BB ($6.80)

Preflop: Hero is MP with J[img]/images/graemlins/diamond.gif[/img], Q[img]/images/graemlins/club.gif[/img]. SB posts a blind of $0.10.
<font color="#666666">1 fold</font>, Hero calls $0.25, <font color="#666666">1 fold</font>, <font color="#CC3333">Button raises to $0.5</font>, <font color="#666666">1 fold</font>, BB calls $0.25, Hero calls $0.25.

Flop: ($1.60) 5[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/club.gif[/img], 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, <font color="#CC3333">Hero bets $1.5</font>, Button calls $1.50, BB folds.

Turn: ($4.60) 8[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $4</font>, Button calls $4.

River: ($12.60) 4[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $6</font>, <font color="#CC3333">Button raises to $12</font>, Hero calls $6.

Final Pot: $36.60