Two U.S. senators are asking Attorney General Eric Holder to investigate whether employers asking for Facebook passwords during job interviews are violating federal law.

Democratic Sens. Chuck Schumer of New York and Richard Blumenthal of Connecticut said Sunday that they are calling on the Department of Justice and the U.S. Equal Employment Opportunity Commission to launch investigations. The senators are sending letters to the heads of the agencies.

The Associated Press reported this week that some private and public agencies around the country are asking job seekers for their social media credentials. The practice has alarmed privacy advocates.

Facebook warned employers on Friday not to ask job applicants for their passwords to the site, saying protected information is often displayed on profiles.