Fan Ejection?

[BSBAL18]

I have read many forums that umpires *can not* eject a fan. He is to talk to the coach about getting his fans under control, but then the text stops there. I am currently looking at the online conflict management stuff thats required by my state, and it refers to conflict management after a fan has been ejected and being alert to exits and where local police may be in case of altercations.

My question is. CAN AN UMPIRE EJECT A FAN? If not, and the umpire has told the coach to get his fans in order, what is the next step if the fan continues? (i am talking about Youth league, but knowing the NCAA/etc rules may also be advantageous for the group in general)