"Britney Spears is dead by accident! We will tell you more soon #RIPBrtiney," the tweet from OurMine read late on Monday.
Alerted, Sony Music immediately swung into action and tweeted after recovering their handle @SonyMusicGlobal: "We saw a new IP logged in to the account a few minutes ago and the tweet is posted by a new IP so @britneyspears is still alive #OurMine".
According to CNET, both the tweets have now been removed from Sony Music Global's account.
Spears' manager Adam Leber was quoted by CNN as saying that the popstar was alive, officially debunking the rumour.
OurMine has hacked into some top-notch Twitter handles in the past, including those of Facebook CEO Mark Zuckerberg, Twitter CEO Jack Dorsey, Niantic head John Hanke and Evan Williams, the co-founder and former CEO of Twitter.
OurMine also hacked into BuzzFeed's website in October and accessed Twitter accounts of Netflix and Marvel.
Sony's movie division was earlier hacked in 2014.
"We don't know who is our next target," OurMine told CNET in an email.