US President-elect Donald Trump is getting plenty of attention — but not the kind he was looking for — after a tweet Saturday calling out China for its seizure of an unmanned US naval probe.

"China steals United States Navy research drone in international waters — rips it out of water and takes it to China in unpresidented [sic] act," the real estate magnate wrote on his favorite platform.

Update: China says it's giving the US its ocean drone back, so stop 'hyping' the incident

"Unpresidented" quickly became a top trending topic on Twitter in the United States, as online wags savaged the incoming president for the unfortunate misspelling.

"Harry Potter" author J.K. Rowling tweeted:

"Dear world, most Americans really wish we could be #unpresidented," another Twitter user wrote.

Trump deleted the tweet after about an hour, replacing it with one correctly using the word "unprecedented."

China steals United States Navy research drone in international waters - rips it out of water and takes it to China in unprecedented act. — Donald J. Trump (@realDonaldTrump) December 17, 2016

While many mocked the deeply divisive political novice, famous for his verbal tics and gaffes, supporters jumped to his defense and said critics were piling on about a typo while ignoring the bigger problem.

Trump was referring to China's seizure on Thursday of an unmanned US naval probe in international waters of the South China Sea, a serious provocation as tensions rise between the two superpowers.

Trump has repeatedly infuriated Beijing in recent weeks, questioning longstanding US policy on Taiwan, calling Beijing a currency manipulator and threatening Chinese imports with punitive tariffs.

The Pentagon on Friday called on Beijing to "immediately" return the probe that it had "unlawfully seized."

Read more: No, Mr. Trump, China did not build a 'massive fortress' in the sea