March 26 (UPI) -- The Federal Trade Commission confirmed Monday it's investigating Facebook's data protection policies.
Earlier this month, it was revealed that data company Cambridge Analytica accessed the information of about 50 million Facebook users without their knowledge.
Cambridge Analytica has ties to President Donald Trump's election campaign.
The FTC now has questions about how Trump consultants got access to Facebook data.
"The FTC takes very seriously recent press reports raising substantial concerns about the privacy practices of Facebook," an FTC statement said Monday. "Today, the FTC is confirming that it has an open non-public investigation into these practices."
The agency previously settled a complaint against Facebook policies. In 2011, it found that Facebook allowed third-party applications to access more data than it needed. Facebook was told to get "express consent" of users before any data, beyond user's privacy settings, was sold or otherwise distributed.
Meanwhile, Sen. Chuck Grassley, R-Iowa, chairman of the Senate judiciary committee, invited Facebook CEO Mark Zuckerberg and the heads of Google and Twitter to testify before the committee about user privacy. He scheduled the hearing for April 10.
The hearing would look into the "standards for the collection, retention and dissemination of consumer data for commercial use" and "what steps companies like Facebook can take to better protect personal information of users and ensure more transparency in the process," a press release said.
Facebook stock fell 14 percent last week as the situation was revealed. It fell another 5 percent in early trading Monday.