Zac Efron issues apology for controversial MLK tweet

Zac Efron didn't mean to offend anyone with his MLK Day tweet, but he's apologizing for it anyway.

The "Dirty Grandpa" star took to social media on Monday to pay his respects to Martin Luther King Jr. on his birthday ... while also celebrating getting to 10 million followers.

SEE ALSO: Zac Efron slammed on social media for 'MLK Day' message

In the since-deleted tweet, the actor said, "I'm grateful for a couple things today: Martin Luther King Jr & 10 million followers on IG."

Almost immediately, fans and non-fans alike replied to his tweet and called him out for not celebrating the two seemingly unrelated events in separate posts. Almost 12 hours later, Efron opened up about his mistake:

In a tweet posted Tuesday afternoon, the star apologized, saying: "I have nothing but the greatest admiration & respect for MLK. My last post was insensitive & I apologize to anyone who I offended. So sorry."

SEE ALSO: Seth Rogen and Zac Efron take on a hard-partying sorority in 'Neighbors 2' trailer

In a separate post sent to the very Instagram followers he celebrated in the original controversy-causing post, Efron expanded his apology:

So, there you have it: Zac Efron screwed up and he's sorry for being insensitive -- though he still hasn't addressed the fact that he's missing the upcoming "High School Musical" reunion.

See photos of Zac Efron from over the years:

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