Concerns are being raised in the U.S. after new evidence came to light involving ICE surveillance of American citizens.

Sen. Richard Blumenthal says he will be demanding answers this week.

“Americans ought to be really afraid learning that ICE is using facial recognition and other surveillance techniques, hacking into their phones and tracing their movements — American citizens surveilled by ICE,” Blumenthal said.

He called the practice a dark watershed moment in American history.

Blumenthal said it signals the steady dismantling of constitutional protections.