The first wave is a NOOSE swat team, after that only regular police trickle in... I used the auto shotgun to clear them out, got in my truck, as you drive off to the north west there is a lot of grass and a baseball field, drive through there as you won't run into any cops, once you're in the clear of the grass you should be out of the wanted area.
Thanks ill try it out.
EDIT: Where exactly is the grass? I see none.