Boston Mayor Michelle Wu drew the ire of the Department of Homeland Security after she criticized U.S. Immigration and Customs Enforcement agents for wearing masks.

Wu told local outlet WCVB on Wednesday that she didn’t know of “any police department that routinely wears masks” like ICE agents do. Instead she pointed out that the neo-Nazi group “NSC-131 routinely wears masks.” As the video of her comments circulated online, it drew a response from DHS, which houses ICE.