Two workers from the Department of Energy’s Idaho National Laboratory lost an undisclosed amount of plutonium and cesium from a rental car parked overnight in a San Antonio, Texas, hotel parking lot in a neighborhood known for car break-ins and other crimes, according to an article published Monday by the Center for Public Integrity.

The loss of the highly radioactive material occurred in March 2017 and was discovered when the two workers awoke the next morning to find the window of their Ford Expedition had been smashed. Missing were radiation detectors and small samples of plutonium and cesium used to calibrate them. The workers were transporting the equipment and materials during an assignment to retrieve dangerous nuclear materials from a nonprofit research lab in San Antonio when the theft occurred. The vehicle had been parked in the lot of a Marriott hotel in a San Antonio neighborhood where car break-ins are common.

More than a year later, state and federal officials still don’t know where the substances are. No public announcement of the March 21 incident was ever made by either the San Antonio Police Department or by the FBI, which police consulted. Officials have declined to say how much plutonium and cesium were taken. A spokeswoman with the Idaho lab told reporters Patrick Malone and R. Jeffrey Smith that the amount of plutonium taken wasn’t enough to create a so-called dirty bomb and that there’s little or no danger from either sources being in the public domain.

Muffing the ball

The missing plutonium and cesium join the ever-growing amount of MUF—short for material unaccounted for—that has resulted from thefts or losses over the years. In 2009, the Energy Department’s inspector general took account of radioactive materials the military loaned to US academic researchers, government agencies, or commercial firms. The conclusion: despite being listed until 2004 as securely stored, one pound of plutonium and 45 pounds of highly enriched uranium were missing. That’s enough material to produce at least five nuclear bombs comparable to those used in the Hiroshima or Nagasaki explosions, the article said. Any amount of plutonium is also highly carcinogenic.

Russia is also believed to have a large amount of MUFs. US officials who have studied Russian accounting of bomb-making materials told the reporters Russian factory logbooks were routinely falsified to match official state-production quota. Accounting irregularities have left officials with the US National Intelligence Council to conclude that undetected smuggling has likely occurred.

San Antonio police said they were surprised that the specialists from the Idaho lab didn’t take more precautions when transporting the material and equipment. The workers “should have never left a sensitive instrument like this unattended in a vehicle,” San Antonio Police Department spokesman Carlos Ortiz said.

Monday’s report said that one of the specialist workers assigned to safeguard the equipment in San Antonio received a “Vision Award” by her colleagues one month after the theft. A few months later, the Energy Department gave an “A” grade and overall performance assessment of “excellent” to Battelle Energy Alliance, the contractor that employed the guards assigned to pick up the nuclear material.