A series of modified AK-47 rifles are etched on a metallic plate that sits behind the statue, including a diagram of what was later revealed to be the German StG 44, designed during World War II.

Moscow-based military historian Yuri Pasholok revealed Thursday in a Facebook post that the rifle diagram etched into the plate is an exact replica of the diagram for the StG rifle.

“Just don’t say that this was an accident,” Pasholok wrote. “One should be beaten, painfully and publicly, for something like this. These are boy-sculptors, dammit!”

Scherbakov acknowledged the discrepancy the same day, admitting that it was a mistake.

“This is a very small background thing,” the sculptor was quoted saying by the RBC news outlet. “I even wonder how they noticed it. We took [the image] from a source where it was written ‘Kalashnikov assault rifle.’”

In 2014 the sculptor was embroiled in scandal after a German Mauser 98 rifle was mistakenly depicted on his monument of a Soviet soldier leaving for the front.