Former Vice President Joe Biden’s presidential campaign has backed away from the his claim that he was arrested while attempting to visit then-anti-apartheid leader Nelson Mandela during a congressional delegation trip to South Africa in the 1970s.

“He was separated from his party at the airport,” Biden deputy campaign manager Kate Bedingfield told the New York Times following Tuesday evening’s Democrat primary debate in Charleston, South Carolina. “They, he was not allowed to go through the same door that the — the rest of the party he was with. Obviously, it was apartheid South Africa. There was a white door, there was a black door. He did not want to go through the white door and have the rest of the party go through the black door. He was separated. This was during a trip while they were there in Johannesburg.”

“When making that remark, he was talking about his long record fighting apartheid; he was one of the leading voices in the United States Senate in the ’80s,” Bedingfield added.

During recently campaign events in Nevada and South Carolina, Biden recalled how he was arrested with the U.S. ambassador to the United Nations in Soweto — despite any public evidence to support the claim. He made no mention of the incident in his 2008 memoir, Promises to Keep.

“This day, 30 years ago, Nelson Mandela walked out of prison and entered into discussions about apartheid,” he told supporters in Columbia, South Carolina. “I had the great honor of meeting him. I had the great honor of being arrested with our UN ambassador on the streets of Soweto trying to get to see him on Robben Island.”

Soweto is located over 700 miles away from Robben Island. Mandela was imprisoned there for 18 of the 27 years he served behind bars before the end of apartheid.

“No, I was never arrested and I don’t think he was, either,” Andrew Young, who then served as U.N. Ambassador, confirmed in an interview with the Times.

Biden’s confusing claim was one of a string of gaffes since he launched his White House campaign in April. During last night’s debate, the former vice president falsely claimed that 150 million Americans have died from gun violence since 2007. Federal government data shows that number is only 156,000 in terms of firearm-related homicides.

On Monday, Biden bizarrely declared in a campaign speech that he is a “candidate for the United States Senate” and that people could “vote for the other Biden” if they prefer another candidate. In the same day, he mistakenly claimed that he worked on the 2016 Paris Climate Accord with former Chinese leader Deng Xiaoping — who died more than 20 years before its enactment.