The Pentagon has authorized the Department of Homeland Security to test a military "heat ray" weapon at the border, lending DHS a vehicle-mounted Active Denial System for seven months in what officials describe as an unprecedented step for immigration enforcement.
Photo: Sgt. Justin Boling / US Marine Corps, Public domain, via Wikimedia Commons
According to a memorandum signed last month by Defense Secretary Pete Hegseth and obtained by CNN, the temporary loan began in September. The Active Denial System fires an invisible beam of electromagnetic energy at targets more than half a mile away. People hit by the beam feel an intense burning sensation, often compared to opening a hot oven, followed by a tingling that can last 10 to 15 minutes. Military officials have described the effect as creating an "instinctive and irresistible urge to run."
The system was developed as a non-lethal crowd-control tool. The memorandum makes clear that the weapon "shall not be operated by" Pentagon personnel, leaving DHS solely responsible for how it is used and for any tactics involved. The memo does not specify where or how the system will be tested.
Customs and Border Protection officials have discussed using the technology for crowd dispersal for years, but it has never been deployed on American soil. The Pentagon considered using the Active Denial System during the George Floyd protests in 2020, a plan that was ultimately dropped amid concerns about turning military equipment on civilians.
Lending the system to DHS marks a new level of military involvement in the administration's border security and immigration crackdown. Civil liberties advocates have long questioned the safety of the heat ray, which was designed for battlefield use, while supporters argue it offers agents a way to disperse crowds without firearms or physical contact.
For now, the loan runs for seven months from September. Whether the tests lead to a permanent deployment at the border will depend on the results — and, likely, on how the public and Congress respond to a battlefield weapon being pointed at the US border.