Hagan later hit back, taking pride in her 'z-list' status: 'You are all thick if u think just because someone's absolutely stunning they won't get cheated on...Cheryl cole? No relationship is perfect.'
Keeping it cool: Rita's recent tweets have been highlighting her holiday in Dubai
She continued: 'Oooopsy getting told off don't shoot the messenger! Of course I'm only a Z-list why would anyone care what I say ;)'
'I only tweeted what I'd seen of lots of other people, I didn't call anyone anything, there is no need for death threats though that's sick.'
Rita was signed to Jay-Z's label Roc Nation over four years ago when she was just 18 and frequently hung out with the rapper's wife Beyonce.
Hagan's claims are not the first time Rita has faced allegations of infidelity.
After her nasty split with Rob Kardashian last month, the reality star accused her of sleeping with 20 men after he reportedly 'got her pregnant'.
'She cheated on me with nearly 20 dudes while we were together... But I mean 20?!!!!' he wrote in the wake of their break-up, before deleting the tirade.
He continued with a series of hateful tweets, including: 'How can a woman who is so busy trying to start her own career have time to be with so many dudes while in a relationship?!'
Rita later fired back in an interview with Glamour magazine, insisting that the couple are still friends and that their relationship severed because of her hectic schedule.
'It didn't work because I was never there,' she said.
'I was like a ghost. I used to get so frustrated with myself and then wonder why I was angry, so I decided it was best to keep it friendly - especially at the moment, when there's so much going on.'
wow! looks like Beyonce has competition.