President Trump mistakenly spelled Marine Corps as “Marine Core” in a tweet Tuesday, sparking ridicule from Twitter users.

Trump was sharing photos of his speech at the Marine Corps Air Station Miramar in California when he made the error.

He deleted the tweet shortly afterward, replacing it with one with the proper spelling.

It was my great honor to deliver a message at the Marine Corps Air Station Miramar to our GREAT U.S. Military, straight from the heart of the American People: We support you, we thank you, we love you – and we will always have your back! pic.twitter.com/oCt1nH3DON

— Donald J. Trump (@realDonaldTrump) March 14, 2018

{mosads}

However, reporters and other social media users quickly picked up on the error.

Some users referred to Trump’s multiple deferments from the draft during the Vietnam War in their tweets. At least one of the deferments was for heel spurs, or bone protrusions caused by calcium buildup.

Oh dear…”Marine Core” https://t.co/AVn8gp6EgC

— Saagar Enjeti (@esaagar) March 13, 2018

“Marine Core” https://t.co/1WgBaVPdVe

— Igor Bobic (@igorbobic) March 13, 2018

lol dork pic.twitter.com/ReXY0KvPeR

— Josh Marshall (@joshtpm) March 13, 2018

Hey Scavino, I’m pretty sure it’s Corps, you should fix that. https://t.co/YwXRHqhcZq

— Matthew Gertz (@MattGertz) March 13, 2018

Maybe start to have their backs by learning to spell “Marine Corps” correctly. https://t.co/OCiDW2htPk

— Chase Masterson (@ChaseMasterson) March 13, 2018

If a Democratic president wrote “Marine Core” it would literally be the central Republican campaign theme. Conservatives would be talking about it 40 years later, like Jimmy Carter “inordinate fear of communism” stories. https://t.co/10mQ6pL9f3

— Jonathan Chait (@jonathanchait) March 13, 2018

People are mocking Trump for misspelling “Marine Corps” as “Marine Core,” but to be fair, since he dodged the draft to avoid serving, he’d never have learned how to spell it. https://t.co/8riMAZBXkz

— (((Yair Rosenberg))) (@Yair_Rosenberg) March 13, 2018

I guess the bone spurs also prevent Trump from spelling “Marine Corps” correctly. https://t.co/Bzvqc8kEkd

— Matthew Yglesias (@mattyglesias) March 13, 2018