The most recent collection of Pentagon UFO files has revealed that mysterious objects have been showing up over US nuclear weapons sites since at least 1949, with none of the incidents formally resolved. This latest release, part of the government's ongoing effort to disclose UFO-related information under the PURSUE programme, is the fourth in the series and the smallest batch, containing 40 documents. Despite its size, it provides the most direct evidence yet that officials have been unable to explain these occurrences at some of the country's most sensitive military locations. The disclosure marks another phase in the government's long-term UFO transparency initiative, which has now made 334 files available to the public in four separate releases.
1949 Los Alamos Conference: Green fireballs and unresolved physics
The oldest file in this latest batch is a stenographic transcript of a classified 1949 conference held at Los Alamos Scientific Laboratory. This meeting followed a string of reports about 'green fireball' sightings above New Mexico’s nuclear facilities. LaPaz made it clear that these sightings were unlike anything he had seen in meteorite drops, effectively dismissing the most likely natural explanation at the time. Teller, on the other hand, proposed a more abstract idea — an 'electron phenomenon' — as a possible explanation. However, no firm conclusion was reached, and the transcript remained under wraps for 77 years before being declassified.
2015 Pantex incident: Silent object and armed pursuit
A 2015 document from Pantex, the nation’s only nuclear weapons assembly site, highlights that sightings of mysterious objects have continued into the 21st century. On 15 September 2015, ground-based radar at Pantex detected a silent, diamond-shaped object. As a result, the facility was placed on lockdown, and armed officers took to the field in vehicles to track the object. They followed it for several miles before ultimately losing its trail. The video footage and witness testimonies were submitted to an FBI agent and to Sandia National Laboratories for further analysis. However, neither agency has shared any findings publicly, and the case remains unresolved.
Another document from the release is a joint study conducted by the US Air Force and Naval Intelligence in December 1948. This research examined approximately 210 sightings and concluded that it would be 'unwise to overlook the possibility that some of these objects may be of foreign origin'. The term 'foreign origin' at that time was a Cold War-era way of referring to the Soviet Union. The study was marked for destruction and remained hidden from public view for 78 years before finally being included in the PURSUE batch. It does not specify the source of the sightings it analyzed and leaves open the question of what exactly was being observed.
The most recent files also contain six video recordings taken between 2023 and 2025 over the Yellow Sea, South China Sea, and East China Sea. One notable 2023 video reportedly captured an object interacting with electro-optical and infrared sensors — the object not only appeared on camera but also seemed to affect the equipment used to track it. A 2025 infrared clip shows an object described as 'an area of contrast resembling a six-pointed star'. Details such as altitude, movement patterns, and origin are all left blank in the documentation, leaving the nature and intent of these sightings unclear.
334 files, zero resolutions
Over four releases through the PURSUE programme and 334 declassified documents spanning from 1948 to 2025, no incident involving a US nuclear site has been publicly closed with a confirmed cause. The 1949 Los Alamos event remains a mystery. The 2015 Pantex incident, which led to a lockdown and armed pursuit, was reported to the FBI and Sandia National Laboratories, but neither agency has provided any conclusions. The 1948 Air Force–Navy study suggested the possibility of a 'foreign origin' but never reached a definitive answer and was slated for destruction. The Pentagon itself has not resolved any of these cases, and all remain marked as unresolved in the accompanying documentation. This consistent pattern of unexplained sightings across seven decades underscores the long-standing enigma surrounding these phenomena and their persistent presence near the most strategic military sites.