Well once u heat level 4-5 they deploy the choppers which will fly over you and watch you

there are 2 ways to get away from them one well is wait for them to refill which takes a few minutes

or you could go through a tunnel which they can't go through since they fly Becareful because even though they appear gone they are just outside however this will help you if you can manuvear good in a tunnel prefabley one with the hiding circle once you have avoided the chopper you still haveto destroy/avoid the cars/suv and since you are in atunnel your room is small so i suggest destroying them. Once they are all gone QUICKLY find the hiding circle and hide there