A set of publicly available flashcards discovered through simple online searches has sparked concern after appearing to reveal sensitive details related to facility security at U.S. Customs and Border Protection locations in Kingsville, Texas.
The flashcards were hosted on Quizlet and compiled under the title “USBP Review” in February. They remained accessible until March 20, when the set was made private shortly after an inquiry was sent to a phone number potentially linked to the account. Although the listed user appeared to be located near a CBP facility, there is no confirmation that the content was created by an active employee or contractor.
CBP has stated that its Office of Professional Responsibility is reviewing the matter, emphasizing that such reviews are routine and do not automatically indicate misconduct. Other agencies under the Department of Homeland Security, including Immigration and Customs Enforcement, did not respond to requests for comment.
If the material is found to be linked to CBP personnel, it could signal a serious lapse for an agency tasked with protecting national borders and safeguarding the country.
The flashcards included what appeared to be access codes for checkpoint doors and specific facility gates, with exact numerical combinations provided in response to direct prompts. Some gate names were not disclosed in reporting due to uncertainty over their confidentiality. Additional entries outlined immigration-related violations such as passport misuse, visa fraud, and attempts to evade checkpoints, along with associated legal consequences.
Several cards also detailed procedural workflows, including voluntary return processes, expedited removals, and warrants of removal. These entries referenced required documentation and reminded users to verify accuracy using an internal “agents Resources Page.”
Quizlet stated that it takes reports of sensitive content seriously and removes material that violates its policies, encouraging users to report concerning sets for review.
Further content within the set described the Kingsville sector’s operational scope, covering approximately 1,932 square miles across six counties. It also explained internal grid and zone systems, noting that one grid designation does not exist due to the layout of regional highways.
The flashcards additionally identified 11 operational towers in the area, including abbreviated naming formats and shared jurisdiction between certain towers. Some of these references appeared to align with the previously mentioned gate locations, increasing the potential sensitivity.
Another entry described an internal system called “E3 BEST,” which enables officers to record, investigate, and process secondary inspection cases. The system allows simultaneous database checks on individuals and vehicles and supports the creation of event records tied to enforcement outcomes.
The incident comes at a time of accelerated hiring across border enforcement agencies. CBP has offered incentives of up to $60,000 to attract recruits, while ICE has promoted similar packages, including signing bonuses and student loan repayment support. Increased recruitment may expand the use of informal study tools, raising the risk of unintended exposure.
Additional searches also surfaced other flashcard sets potentially linked to DHS-related training. These included materials on detention standards and transportation procedures, with prompts such as detainees being transported in a “safe and humane manner” and rules stating that driving under the influence is prohibited. Another set appeared to contain answers to internal training questions, including multiple-choice responses such as “Both A and C” and “All of the above.”
One user created more than 60 flashcard sets between November 2025 and February 2026, covering topics from radio codes and alphabets to more advanced areas like body-worn camera policies and immigration-related Spanish vocabulary. A more recent set included terms resembling language used in recruitment messaging, such as “the nation,” “the security,” and “the homeland.”
From a broader security perspective, the incident highlights how publicly accessible platforms can unintentionally expose operational knowledge. While no confirmed misuse has been reported, the situation underlines the importance of controlling how internal training materials are created, shared, and stored, particularly within agencies responsible for national security.
