Zac Efron is now in hot waters after he posted a controversial tweet about Martin Luther King Day. The "High School Musical" star seemed to be celebrating the holiday which honors the late civil rights movement leader on Monday but people think he's gone too far.

"I'm grateful for a couple things today," Zac 28, posted alongside a photo of himself sporting aviators and cruising down a palm tree-lined street at dusk on Twitter. "Martin Luther King Jr & 10 million followers on IG."

The "Neighbors" actor added pointer finger and fist sign emojis and used the hashtag "#MLKDay." Several followers and detractors alike called out Zac's post with memes and mixed reactions.

 "@ZacEfron Zac I ❤️ you, but whichever social media manager told you gaining 10 mil followers and MLK's work are in the same vein, fire them," one Twitter user said. "@ZacEfron This is one of the most offensive/diminishing/disrespectful things anyone has said in relation to MLK today. Get over yourself.," another user commented.

After receiving several backlash from netizens, Zac was quick to say sorry to everyone who got offended by his controversial post. I have nothing but the greatest admiration & respect for MLK," the "Neighbors 2: Sorority Rising" actor tweeted on Tuesday. "My last post was insensitive & I apologize to anyone who I offended. So sorry."

Meanwhile, the first trailer for Zac's upcoming comedy sequel was released on Tuesday. The plot focuses on the actor, together with Rose Byrne and Seth Rogen, to take down a sorority headed up by Chloe Grace Moretz.