A United States Marine Corp-affiliated Twitter account on Friday tweeted (and later deleted) a message commemorating Martin Luther King Jr. Day — and “lone shooters.”

“Don’t be lone shooter #MLK weekend — make sure you’ve got security!” the U.S. Marine Corps Forces Special Operations Command (MARSOC) account tweeted Friday morning.

The tweet was accompanied by a photo of a Marine standing at a window with short barrel rifle:

OH NO: USMC Affiliated Twitter Account Sends Out Regrettable MLK Day Lone Shooter Tweet

Image source: Mediaite

The account immediately deleted the tweet and went silent for a few hours before issuing the following statement:

In case you’re not sure why people were shocked by the tweet (shocked enough to prompt a deletion and an apology), Martin Luther King Jr. was assassinated by a lone gunman on April 4, 1968. The gunman, James Earl Ray, shot and killed King with a rifle.

(H/T: Mediaite, BuzzFeed)

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