A pair of Hispanic Democratic congressmen are demanding that top immigration officials give them details about arrests made in the past week during the Immigration and Customs Enforcement raids ordered by President Donald Trump.

In a letter Wednesday to acting Homeland Security Secretary Kevin McAleenan and acting ICE Director Mark Morgan, first obtained by NBC News, Assistant House Speaker Ben Ray Luján of New Mexico and Congressional Hispanic Caucus Chairman Joaquin Castro of Texas asked for extensive information about those arrested.

The Trump administration began the immigration raids last weekend as part of an operation that was expected to target about 2,000 immigrants in up to 10 cities. The number of people arrested in the raids, which had been scheduled to take place weeks earlier but were postponed, has not been disclosed.

The details Luján and Castro requested include the names, ages and congressional districts of those detained, whether they had family members who were citizens or permanent residents, how long they’ve lived in the United States, whether warrants were secured and their “manner of apprehension.” They also pressed officials on the number of “collateral arrests” — people who were not targeted for arrest but were swept up during the raids.

The lawmakers also asked the officials whether those arrested had pending immigration filings with the U.S. Citizenship and Immigration Services, the type and status of those filings, where the persons arrested were currently being detained, their expected date of deportation, and whether they had access to legal counsel in detention.

“The Administration’s plans to execute large-scale, coordinated enforcement operations and ongoing efforts to publicize inhumane family separations have caused significant anxiety, fear and trauma for American families and discord for citizens and migrants alike,” Luján and Castro wrote. “We are deeply concerned that as ICE continues to expand use of aggressive enforcement operations, immigrant families will go without due process protections, and that bystanders who are not on ICE’s list but are merely ‘suspected’ of being undocumented will be caught up in the raids.”

The pair of lawmakers also warned that the raids "will continue to cause unnecessary trauma to vulnerable family members, including minor children, and United States citizens.”

The letter asked how the raids were funded, formal procedure protocols for reporting ICE personnel misconduct, and the number of people apprehended for whom there had been court-ordered removals.

McAleenan is set to testify Thursday in front of the House Oversight and Reform Committee about the Trump administration's treatment of immigrants detained at the U.S.-Mexico border, including family separations.