As the Trump administration prepares to potentially declare a national emergency to jumpstart construction of a wall along the U.S.’s southern border—as well as possibly using storm aid funds to do so—the viability of the wall itself has come under fire. In a photo obtained by NBC News, one of the steel bollard border wall prototypes in Otay Mesa, California, was easily breached using an off-the-shelf saw.

The eight border wall prototypes in Otay Mesa (directly across from Tijuana in Mexico) were assembled in early 2017 after an executive order directed the Department of Homeland Security to design and build a southern border wall. Four concrete wall segment mockups, and four from mixed materials, were assembled in the desert. The 30-foot-tall prototypes were graded on their aesthetic qualities in August 2018, but testing in late 2017 has revealed that all eight may be easy to penetrate.

Dept. of Homeland Security testing of a steel slat prototype for border wall proved it could be cut through with a saw, according to a report by DHS. A photo obtained by @NBCNews shows the results of the test. https://t.co/SNxn6YneG9 pic.twitter.com/UP9EgHGxDx — NBC News (@NBCNews) January 10, 2019

On “Pogo Row”, a testing area near the California-Mexico border, Customs and Border Protection (CBP) agents were instructed to try to breach the eight border wall segments—and eventually broke through all eight. Using saws and other hand tools, teams were able to cause holes “larger than 12-inches in diameter or square,” the DHS standard definition of breaching.

According to a redacted version of the CBP report obtained through a freedom of information request from the San Diego-based KPBS, replicas of each prototype’s first ten feet were tested for breaching. One (redacted) technique proved so destructive during the first test that further experimenting was postponed, as officials feared it would destabilize the structural integrity of the other models before they could be thoroughly assessed.

No testing on how well the walls were able to resist tunneling appears to have been conducted, despite that being a major design criterion in the Request for Proposal. Additionally, none of the eight designs met the requirements for adaptability across the thousands of miles of the border’s rugged, varied terrain.

For its part, the DHS has argued that no wall is impenetrable and that by slowing migrants trying to breach it, Border Patrol agents are given time to respond. DHS spokeswoman Katie Waldman told NBC that the prototypes were only meant to inform the final design moving forward.

When asked about the photo obtained by NBC yesterday, President Trump responded that, “that’s a wall designed by previous administrations.” While previous administrations have used steel bollards at the border, the prototypes tested were built by the Trump administration.