I would not risk myself being mugged, shot, bruised, cut or whatever ...just to save my spare tire. life is too precious.

1st - try to find somebody..guards, police, etc to get for help.
2nd - try to set your car alarm to 'panic' mode to sound the alarm ang get attention. And hopefully chase them away.
3rd - make sure you identify the persons and get away vehicle so that you can report later to the authorities.