Former Vice President Joe Biden stumbled over his words while addressing voters in Iowa earlier this week.

Biden, who has been plagued by a recent string of high-profile gaffes, became tongue tied when mentioning “a longtime friend” at a campaign appearance in Urbandale, Iowa on Tuesday.

“My long friend time friend, and she’s a friend, she’s been my friend, in and out of public life,” Biden said to awkward applause from the crowd.

I think there’s a friend that @JoeBiden’s known a long time in and out of public life. . . Just helping translate this. pic.twitter.com/7jbXxAJ9jU — Ned Ryun (@nedryun) August 23, 2019

At the same event, the 76-year-old former vice president inaccurately claimed that Robert F. Kennedy and Martin Luther King, Jr. were assassinated in the 1970s.

“Just like in my generation, when I got out of school, when Bobby Kennedy and Dr. King had been assassinated in the ’70s — the late ’70s — I got engaged,” Biden told the audience, before proceeding to ramble about the counter-culture movement of the 1960s.”

The claim was quickly called out as false, as both men were assassinated within mere months of each other in 1968 — a turbulent year in American history. The confusion was especially troubling for Biden, who has often cited both men as big influences on his decision to enter politics. Biden was supposedly so taken with Kennedy, whom he once called “the one true hero of my life,” that he plagiarized substantially from his fallen hero during the 1980s.

This is not the first time Biden has tripped over his words in public. Last month, at the second Democrat presidential debate, Biden delivered a gaffe-ridden and at time perplexing closing statement.

“This most consequential election anyone of you, no matter how old or young you are, has ever participated in…. Eight more years of Donald Trump will change American in a fundamental way,” Biden said. “The America we know will no longer exist.”

“If you agree with me, go to Joe 3-0-3-3-0, thank you very much,” he added, likely meaning to describe how supporters could reach his campaign.

Such prominent verbal missteps have raised doubts from both Biden’s allies and opponents regarding his fitness to run a modern presidential campaign.