Eminem unleashes on Machine Gun Kelly in brutal diss track 'Killshot'

Eminem has continued his vicious feud with rival rapper Machine Gun Kelly (MGK), releasing a new diss track entitled 'Killshot'.

The 45-year-old hop-hop star makes a number of violent threats in the track, as well as insulting the younger musician over his appearance, lyrical abilities and album sales.

Eminem also appears to allege that hip-hop mogul Diddy is responsible for the murder of Tupac in the track - although assures Diddy he's "just playing".

'Killshot' is a response to MGK's 'Rap Devil', which itself was a response to 'Not Alike', a track on Eminem's Kamikaze album.

In an interview released just a few days ago, Eminem said 'Rap Devil' had some "good lines in it" and that it was "not bad, for [MGK]".

In the lyrics of 'Killshot', however, he says he's "perplexed" by what he sees as mixed messages in the track.

"Wait, you just dissed me? Insult me in a line, compliment me on the next," raps Eminem.

"Younger me? No, you're the whack me, it's funny but so true - I'd rather be 80-year-old me than 20-year-old you.

"My biggest flops are your greatest hits... as I'm Shady, he's gon' have to live in my shadow."

Before MGK released 'Rap Devil', he posted a video on Instagram of himself dancing to Eminem dissing him in 'Not Alike', while spraying sparkling wine out of a bottle.

This is also referenced by Eminem in 'Killshot', as he suggests this feud will be the high point in MGK's career.

"Yeah, bitch, pop champagne to this, it's your moment," raps Eminem.

"This is it, as big as you're gonna get, so enjoy it. [I] had to give you a career to destroy it!"

MGK is signed to Bad Boy Records, which is run by Diddy, aka Puff Daddy.

It is the record label the Notorious B.I.G. was signed to in the '90s during the infamous East Coast / West Coast feuding that led to the murders of the 'Juicy' hitmaker and his friend-turned-rival, Tupac.

Perhaps the most shocking content in 'Killshot' comes when Eminem references Diddy.

"This idiot [MGK]'s boss pops pills and tells him he's got skills," raps Eminem.

"But, Kells, the day you put out a hit is the day Diddy admits that he put the hit out that got 'Pac killed."

MGK is yet to reply on social media to this latest round in his feud with Eminem, but other musicians have been quick to declare the older rapper the winner.

Still others - including Iggy Azalea, who is also insulted in 'Killshot' - are criticising Eminem for the track, too.