Hundreds of immigrant advocates gathered outside a federal courthouse here Monday as local officials from across Texas squared off for a legal showdown with the state and federal governments over the state’s new anti-“sanctuary city” law.

Mayors, council members and county judges from tiny border towns and big Texas cities were packed inside. One by one, their attorneys called for U.S. District Judge Orlando Garcia to temporarily halt implementation of Senate Bill 4, which aims to force local municipalities to help detain immigrants in the country illegally.

Read more in the Los Angeles Times.