Oh Noah!..
Listen its too late to turn the clock back, but i would call everyone you can that is nearby to go and check around and try to see what is going on.. I dont think they should go and knock on the door as this group seem hostile!
Secondly do you really want such large groups in your house like a party style? you can select what types of groups you want and dont by sufficient correspondence to make sure they are the types of people to take care of your home and be respectful.. you can learn a lot by chatting but of course not full proof.
Anyway, getting the police involved may make them react, all you can do is call police after if any damage is done and give details. then put in complaint to airbnb with costs to guests.
lastly never ever say you are miles away!... i always say i am just popping out even if i am working overnight.. or i say IF i have to go to work i can be reached and will be back later... My guests never know i am going to be out all night for work or sometimes for 2 days!... i keep them on their toes..lol
But i think you have to go home and check it out now and take some friends with you to sit in the car also if you feel unsafe with these guest..
Good luck
Mala