Workers in Moscow have cut out part of a new monument to a Russian creator of the world famous AK-47 assault rifle because a weapon depicted on the statue was actually a German-designed firearm.
Mikhail Kalashnikov's monument was opened this week to great fanfare by government officials and members of the Russian Orthodox Church.
But arms experts said a drawing on the base of the statue showed the StG 44 rifle used by the Nazis during WWII.
It was removed by an angle grinder.
"A mistake has been made by the sculptor," executive director of the Russian Military Historical Society Vladislav Kononov was quoted as saying by Russian news agencies.
The society commissioned the 7.5m (25ft) monument, which shows Kalashnikov holding an AK-47 in his arms.
A series of modified AK rifles were etched on a metallic plate on the base of the statue, including the wrong drawing.
Russian arms historian Yuri Pasholok was the first to point out the error, and several experts later confirmed this was the case.
Sculptor Salavat Shcherbakov said earlier on Friday that "this is something we're correcting", adding that "we're trying to avoid mistakes", Russia's Rossiya-24 TV channel reported.
The automatic rifle is one of Russia's most celebrated weapons, with Culture Minister Vladimir Medinsky describing it as the country's "cultural brand".
Designed by Kalashnikov in 1946, it became one of the world's most familiar weapons used in virtually every major conflict.
Its comparative simplicity made it cheap to manufacture, as well as reliable and easy to maintain.
Although honoured by the state, Kalashnikov himself made little money from his gun. He once said he would have been better off designing a lawn mower.
He died in 2013 at the age of 94.
The StG-44 (Sturmgewehr 44) was invented by Hugo Schmeisser and first used by Adolf Hitler's troops in 1944.
Some experts point to the similarity of the StG-44 and the AK-47, and also mention the fact that Schmeisser - together with a group of German engineers - was forced to work in the Soviet Union after World War II.
Mystery surrounds design of the AK-47
By BBC's Jonathan Marcus
The AK-47 assault rifle and its variants equipped the Soviet Red army and became the iconic weapon of popular revolt and insurgency throughout much of the world. It was manufactured in huge numbers in several communist countries.
The story that it was the brainchild of the lowly Sergeant Mikhail Kalashnikov made great Soviet propaganda, but the origins of the design remain a mystery.
The first automatic weapon of this kind - the Sturmgewehr 44 - was developed by the Germans during the latter part of World War Two. It was well known to the Russians who also benefited from the expertise of captured scientists like Hugo Schmeisser, the man who designed the Sturmgewehr.
Developed at a time of extraordinary Stalinist secrecy we will probably never know. Many people may have had critical inputs into the weapon's design but it is by the Kalashnikov name that it will always be known.