The detentions have become a relatively easy way for Immigration and Customs Enforcement agents to detain immigrants who are appearing for court dates.

Civil rights groups sued the Trump administration on Wednesday in a bid to stop the government’s policy of allowing Immigration and Customs Enforcement officers to arrest undocumented migrants who show up for immigration hearings at courthouses.

A class-action lawsuit seeks to stop ICE officers from arresting migrants who appear at immigration courts and placing them on a fast-track to deportation.