There are several routes: an order of protection or no-contact order, a petition in the existing custody case, pressing criminal charges so a no-contact bond condition is entered, and reporting the conduct to DCFS.
Each option has consequences, including consequences for you, and they are not interchangeable. Discuss them with an experienced attorney before filing.
If a child is in immediate danger, call the police in that town and request a well-being check now, not after paperwork is filed.