The @foxnewspolitics feed stated: "@BarackObama has just passed. The President is dead. A sad 4th of July, indeed. President Barack Obama is dead."
Just an hour before the message, there was a post "Just regained full access to our Twitter and email. Happy 4th". July 4 is America`s national day.
Even nearly three hours after the last twitter update on the account wishing luck to the "new" President John Biden, none of the messages have been removed.
Reporting that hackers have taken over a Twitter account belonging to Fox News, BBC said a group or individual, calling themselves `The Script Kiddies` appeared to claim responsibility.
Fox News Politics is one of the Twitter accounts associated with the industry-leading cable news network, the BBC said adding its Twitter account carries the "verified" tick icon, indicating that the feed belongs to the organisation it claims to be.
The twitter account that one get to see on the channels website @FoxNews follows the account of @foxnewspolitics.
BBC said it is unclear why Fox News has been attacked in this instance. "However, the broadcaster`s conservative stance has made it unpopular with many Americans."
Fox News is said to be the most watched cable news network in the United States, with its prime time shows attracting almost two million viewers, well ahead of rivals CNN and MSNBC.
An attack on another Fox Entertainment Group website, Fox.com was the first confirmed hit by hacker group Lulz Security in May 2011, BBC said.