creaking sound

I noticed few days ago when I park my car , shut the engine down and don't apply parking brakes my vehicle makes creaking metallic noise.
When I push the car by hand sound comes from front and is present only with transmission selected to "Park" and brakes off. Any other transmission gear selection and the noise is gone.
The car drives well otherwise.
I have no clue what that can be.
Thanks for help

Les
2013 Mazda6 2.5