50 Cent has been slammed by hip-hop fans for joking about Beyoncé Knowles and Jay-Z’s new baby.

The couple welcomed their first child, daughter Blue Ivy, into the world on Saturday and are thought to have left the New York hospital Beyoncé was recovering in last night.

Not long after the birth was reported, 50 Cent took to his Twitter to joke about the pair’s new arrival. The rapper posted a picture of a baby’s body with Jay-Z’s face superimposed, with an accompanying caption.

‘Yal play to much congratulations to JAYZ and Beyonce BABY #BlueIvyCarter IS GEORGOUS @50cent (sic),’ he wrote on his page before adding: ‘You bull sh*ting they will pay a million dollars for a picture of that baby lol trust me.’

Many fans took to the social networking site and internet forums to show their disdain at the mocking picture.

‘lmfao s*** is just wrong on so many levels WTF (sic),’ one user wrote.

50 Cent has famously offended Jay-Z in the past, after vowing to steal Beyoncé from him. He also said the star was “only famous for marrying Beyoncé’ and ‘outside the States and hip-hop circles no one really knew who he was until that”.

50 Cent has been using his Twitter page to vent a lot of frustration of late.

The hip-hop star made an apology to the bosses of his record label after he accused them of leaking one of his songs.