The New York Post said Thursday it had been "hacked" by an employee after the tabloid newspaper’s Twitter account posted a series of antagonistic messages, including a call for the assassination of US President Joe Biden.

The rogue tweets were removed late Thursday morning. 

"The New York Post has been hacked. We are currently investigating the cause," a message on the tabloid’s account said.

"The New York Post’s investigation indicates that the unauthorized conduct was committed by an employee," the Post said in a statement to AFP, adding that the worker in question had been fired.

The tweets, published Thursday morning, included a call for the assassination of Biden, along with a demand to kill New York lawmaker Alexandria Ocasio-Cortez. 

The messages were formatted to look like normal tweets usually posted by the newspaper, which is owned by NewsCorp, the media empire owned by Australian billionaire Rupert Murdoch. 

One tweet -- which relied on racist cliches to criticize New York Mayor Eric Adams, who is Black -- linked to an article on the paper’s site with the same title as the tweet text, according to BuzzFeed News reporter David Mack, which he said suggested the hacker had some kind of inside access to the Post’s content management system. 

"The employee has been terminated," the newspaper said in its statement. 

"This morning, we immediately removed the vile and reprehensible content from our website and social media accounts."