Sorry, guys, but if you are unarmed (or armed, but don't have time to draw) you have to run.
No matter how good you are at any kind of martial art, you are outnumbered and it takes only one lucky strike on their part (or one screw up on yours) for you to go down. You don't know what they are carrying, or whether they have pals in the vicinity.
And like many say, once you are down, you are done.
I spent many years in a very rough trauma unit. I've seen many guys come in, beaten up. Often they were beaten up by more than one assailant. I never saw a guy come in with bloodied knuckles and slight injuries, telling me to look out for the six guys he just defeated, who should be arriving shortly on stretchers
It is my opinion that there are more advantages to running (even if it is just to buy time and distance) than to stay put and square up to them.