Barack Obama’s campaign staff is scrambling to explain a family story Obama told on the campaign trail that rivals say is untrue and warrants explanation.

At a Memorial Day campaign stop Obama told a story about his WWII veteran uncle who allegedly liberated Auschwitz. Upon returning to the United States, according to Obama family lore, the uncle spent months alone in his attic. “Now obviously, something had really affected him deeply, but at that time there just weren’t the kinds of facilities to help somebody work through that kind of pain,” Obama said. “That’s why this idea of making sure that every single veteran, when they are discharged, are screened for post-traumatic stress disorder and given the mental health services that they need – that’s why it’s so important.”

The trouble is, the Red Army liberated Auschwitz and Obama’s mother is an only child. (His father left him at a young age, so it was unlikely the uncle in question was related to his father.)

The Republican National Committee and members of the media seized on the story, demanding clarification. RNC spokeswoman Liz Mair said in a statement: “Barack Obama owes the American public an explanation in light of his statement yesterday regarding his uncle and the liberation of Auschwitz. It is a well-known fact that Soviet troops liberated Auschwitz. Unless Obama’s uncle served in the Red Army, his statement looks nothing short of fatuous—and Americans expect something better than exaggerations and outright distortions from a candidate who hopes to become our next Commander in Chief.”

Shortly after, an Obama campaign spokesman said Obama did have a great uncle who helped liberate a different war camp. The campaign said Obama’s great uncle on his mother’s side, Charlie Payne, was a member of the 89th Infantry Division that liberated Buchenwald in 1945.