Interesting hand from Stars $10 rebuy

[Whitey]

No hand history so I'll try and remember it as best I can.

Blinds : 600/1200 with an ante ( about 50 at this level I think )

Hero 70k
villian 70k

Villan has been raising liberaly since getting lucky with TT vs AA when he moved all in pre flop for 50k when no one else had opened.

I have seen him push all in with 40k 50k and 60k at this level and showed a medium pocket pair every time.

He has open raised for 3XBB several times then folded when either re-raised or missed the flop and someone has played back at him.

So the hand.

MP2 (villan) open raises for 3600
MP3 (hero) Flat calls with 77

everyone else folds

Flop 55T with 2 diamonds

Villian bets 3k Hero calls

Turn Js

Villan bets 4k Hero calls

River Jd putting 3 to the flush and two pair on board

Villan bets 30K! Hero ???