A congressional committee wants information on the Trump administration's plan to send TSA employees to the U.S.-Mexico border to assist with immigration enforcement.
A TSA spokesman confirmed the agency was "in the process of soliciting volunteers" last week.
In a letter sent Monday to the TSA's administrator, two Democratic members of the House Oversight and Reform Committee wrote, "We are deeply concerned that pulling hundreds of TSA employees away from their critical missions at our nation's airports and sending them to the southern border will weaken aviation security."
A TSA official already acknowledged in an internal email obtained by CNN that shuffling personnel to the border during the peak summer travel season comes with "some risk."
Last year, TSA officers screened a record 253 million airline passengers and crew members between the Wednesday before Memorial Day and the Tuesday after Labor Day.
The email reportedly said TSA workforce sent to the southern border is not expected to initially include uniformed airport screeners. Instead it'll be people with more behind-the-scenes security jobs. An unnamed source told CNN that air marshals could also be pulled.