The Department of Housing and Urban Development is suing Facebook for violating the Fair Housing Act. HUD says Facebook allows companies that advertise housing on the social media platform to block their ads from select groups of users based on factors such as race, religion, gender and disability. Some of the categories available to advertisers include “foreigners,” or people who selected “Hispanic culture” or “hijab fashion” as an interest. Facebook says it is working on the issue; last week the company reached a settlement with civil rights groups, agreeing to overhaul its microtargeting system to curb discriminatory advertisement. HUD is reportedly also reviewing Twitter and Google’s targeted advertising practices.