(CNN)The Department of Homeland Security is shifting personnel from various agencies to the southern border to assist with the surge of migrants arriving from Central America, according to DHS officials.
The shift in resources includes the deployment of around 200 employees who have volunteered from throughout the department, according to administration officials.
Additional federal employees have volunteered and the department is now going through the process of figuring out how to get them to the border, said an administration official.
This is a small segment of the more than 240,000 person DHS workforce, and does not include the hundreds of Customs and Border Protection employees who have already been transferred from other positions to help on the US-Mexico border.
Volunteers include personnel from the Transportation Security Administration, the Federal Emergency Management Agency and US Secret Service. However, all DHS component agencies were asked to provide volunteers.
The ranking member of the Senate Homeland Security Committee, Sen. Gary Peters, was critical of the moves, saying that "Congress must address the challenges at the Southern border without jeopardizing security at the Northern border or any of DHS' other critical national security missions."
"Transferring resources and personnel from other vital agencies like TSA or FEMA are short-sighted, temporary fixes that could have serious ripple effects across the country, such as longer wait times at airports during the busy summer travel season or reduced capacity for disaster response during hurricane season," he said in a statement.
DHS has maintained that is is still capable of maintaining operations, despite the reshuffling of resources to address the situation at the border.
The call for volunteers and additional resources comes as the number of illegal border crossings is spiking, with apprehensions at a 10-year high. DHS officials have repeatedly said the department's current resources are not equipped to deal with the increase of families and children arriving at the border.
Less than two weeks later, Nielsen was ousted from her role and replaced by CBP Commissioner Kevin McAleenan, who has continued to call for additional department resources.
As of Tuesday, TSA had deployed approximately 100 personnel to the border, according to a DHS official. TSA volunteers will provide transportation, meal distribution and legal support, but will not conduct immigration duties at ports of entry, the official said.
"There is now immediate need for more help from TSA at the SW border," a senior TSA official, Gary Renfrow, wrote in the email to agency regional management, which was obtained by CNN. "TSA has committed to support with 400 people from Security Ops" who will be deployed in waves "similar to support for past hurricanes."
To date, US Citizenship and Immigration Services has deployed 40 volunteers to assist DHS at the border, according to a USCIS official. The volunteers span across the agency's directorates and offices.
When asked about the staffing changes, a Homeland Security spokesperson said the department "is considering all options to address the humanitarian and security crisis at our southern border. We will continue to work with our workforce to find dynamic solutions and funding to address this very serious problem."
As part of the call for volunteers, the Secret Service has deployed non-law enforcement personnel to the border and the Federal Protective Service has deployed law enforcement personnel to the border to support CBP with "general law enforcement duties," according to the DHS official.
Homeland Security has what's known as the "volunteer surge force," which is usually maintained by FEMA for hurricanes and other natural disasters, said an administration official, and the department is now using it as a model to try to surge folks on volunteer basis to help with the influx of migrants.
FEMA initially provided technical assistance and deployed teams to the border to assess and coordinate mass care and voluntary support requirements, according to a spokesperson for the agency. Those teams demobilized once those assessments were complete in late April.
"Some FEMA employees have volunteered to work at the border as part of the department-wide call for volunteers," the spokesperson said.