Madonna Rebel Heart: Pharrell Williams collaboration and 13 more songs leaked

Singer released six tracks on iTunes just one week ago

Madonna is not in Twitter's good books after describing her album leak as 'artistic rape and terrorism' (Getty Images)

Madonna has been targeted in another online leak, just days after she was forced to release six tracks from her Rebel Heart album.

The 56-year-old pop star released the songs after 13 unfinished demos appeared online earlier in December, including Rebel Heart, B***h I’m Madonna and Unapologetic B***h.

Now, 14 more tracks have also been released into circulation without Madonna’s permission, including include Tragic Girl, Beautiful Scars, Iconic and Freedom, Billboard reports.

The songs also include a collaboration between Madonna and Pharrell Williams called Back That Up (Do It).

The furious singer controversially branded the first leaks “artistic rape” and a “form of terrorism”.

In a now-deleted Instagram post, the artist reportedly wrote: "This is artistic rape!! These are early leaked demo's half of which wont even make it on my album the other half have changed and evolved. This is a form of terrorism. Wtf!!!! Why do people want to destroy artistic process??? Why steal? Why not give me the opportunity to finish and give you my very best?"

In another post, Madonna thanked her fans who chose not to listen to the unauthorised tracks, writing: "Thank you for not listening! Thank you for your loyalty! Thank you for waiting and if you have heard please know they are unfinished demos stolen long ago and not ready to be presented to the world.”