No-one has claimed responsibility for the prank (supplied).
In what has been dubbed the Big Mac of hacks, a prankster took control of Burger King's Twitter account and told the fast food chain's 89,000-plus followers the company had been sold to McDonald's.
The hacker made the restaurant's Twitter page resemble that of its rival McDonald's around 4am (AEDT) this morning.
" We just got sold to McDonalds! Look for McDonalds in a hood near you @DFNCTSC," the hacker posted.
The online mischief maker also posted disparagingly about Burger King's employees.
"We caught one of our employees in the bathroom doing this….", read one post accompanied by a photo of a man sinking a syringe into his arm.
The prankster even tweeted threatening messages to potential customers.
"If I catch you at a wendys, we're fightin!," the hacker wrote.
Twitter users suggested that McDonald's could have been behind the hoax, prompting the fast food giant to respond.
"We empathize with our @BurgerKing counterparts. Rest assured, we had nothing to do with the hacking. " McDonald's tweeted from its official account.
Burger King Worldwide Inc. spokesman Bryson Thornton said the company had contacted Twitter, who have suspended the account.
Burger King firm plans to post an apology on Facebook and have its account back up soon.
Source: Twitter, New York Post
Author: Martin Zavan, Approving editor: Mark Worley