Protesters demonstrate outside an FBI office in Milwaukee on Saturday after agents arrested a county judge accused of helping a man evade immigration authorities.

The arrest marks a significant escalation in the Trump administration's crackdown on immigration, as well as in its battles with judges across the country.

A Wisconsin judge is now threatening not to hold court after the FBI arrested Milwaukee-based Judge Hannah Dugan on Friday on obstruction charges. Judge Monica Isham of Sawyer County made the stunning claim in an email sent to all state judges on Saturday,