Rep. Jamie Raskin (D-Md.) has warned that Immigration and Customs Enforcement (ICE) raids could sweep up “innocent citizens.”

“If you’re not out looking for criminals based on crimes committed, but undocumented immigrants based on their looks, you’re going to sweep up a lot of innocent people, including innocent citizens,” said the Maryland Democrat, according to a statement obtained by NBC News.

“We’ve already seen cases of racial and ethnic profiling leading to the unlawful detention of U.S. citizens. That’s why I’m demanding answers about some of these profoundly troubling stories we’ve heard about citizens being targeted, detained and questioned,” he added.

Raskin and Rep. Pramila Jayapal (D-Wash.) also sought answers from acting ICE Director Caleb Vitello and Department of Homeland Security (DHS) Secretary Kristi Noem on “troubling reports that U.S. citizens have been detained during immigration enforcement operations” in a Tuesday letter, of which NBC News obtained a copy first.

“A recent NBC News article highlighted multiple incidents in which American citizens were wrongfully detained during immigration enforcement raids,” the two progressive Democrats wrote. “Additionally, Telemundo Puerto Rico recently reported on three U.S. citizens in Milwaukee—a toddler, his mother, and grandmother—who were detained and transported to an immigration detention center.

ICE has denied the Milwaukee incident, claiming it was “completely false,” according to the Milwaukee Journal Sentinel.

“These reports raise serious questions about the actions of Department of Homeland Security (DHS) and Immigration and Customs Enforcement (ICE) personnel when conducting immigration enforcement,” Raskin and Jayapal said.

The Hill has reached out to DHS and ICE for comment.