I hate those turn cards

[SGS]

I have KK in the BB of the 10r on stars. I have ~25000 chips and the SB has me covered with 28k. The big blind is 800. It's folded around to him and he mine raises to 1600. I then make it 4k. He calls. SB seemed pretty tight thus far.

FLOP 235 two hearts

He checks I bet 6000 he calls.

TURN Ao

HE checks, what action do you take? I have 15k behind and the pot is currently ~20k. Thanks in advance.

SGS