If you believe your life or limb is threatened you may want to file a police report. If the land is not yours then you probably don't have standing to do anything about the alleged trespass.
The information you obtain from this answer is not, nor is it intended to be, legal advice. You should consult an attorney for advice regarding your individual situation.
I agree with Ms.. Henson...file a police report. This is not a nuisance issue...its a criminal one. Since these people are using property that does not belong to them, you can also contact the owner of that property and let them know what is happening so they can seek to remove these people.
Since this is happening on property not owned by you, how did you come to be threatened to be ran over?