Wray told members of the House Homeland Security Committee in a hearing about worldwide threats on Tuesday that he is “extremely concerned” about TikTok’s operations in the U.S.

“They include the possibility that the Chinese government could use it to control data collection on millions of users. Or control the recommendation algorithm, which could be used for influence operations if they so chose. Or to control software on millions of devices, which gives it opportunity to potentially technically compromise personal devices,” Wray said.

Walden said she is concerned not only as a White House official but as a parent.

“In the context of TikTok, this is personally of interest to me because I have teenagers who spend their entire lives on TikTok and because it is so absorbing, but you do wonder about the Chinese government’s motivation in feeding all of that information stream to millions of Americans. And then also all the tracking that goes along with that,” Walden said. “So you talk about safety has to be a priority, but if Beijing has very different priorities than you do, how do you consider this massive influence operation that China is running on TikTok for millions of Americans, at the same time they’re having a very different perspective on what they want the outcome to be.”