Los Angeles - Selena Gomez allegedly branded Justin Bieber a "drug addict" and urged him to "go to rehab".
The singer-and-actress - who is believed to have rekindled her romance with the Believe hitmaker - lashed out at the 19-year-old star in a text message row which saw him send her x-rated nude photographs.
The messages, which were reportedly forwarded from a phone registered to Selena's stepfather, Brian Teefey, to one of her friends, begin with Justin saying: "Baby come on. I love you."
However, his on/off girlfriend responded with a furious attack, writing: "I don't buy that bullshit any more. I was honest with you and I gave you a second chance. All my friends were right, You're such an asshole."
Justin replied: "You're all I need right now. I know I can make it right with you."
Selena hit back, writing: "U r a drug addict. U need help."
'I hope you get jail time'
According to RadarOnline.com who obtained the messages, Justin then sent a photo of his manhood, writing: "Come on. Don't tell me you don't miss this."
Selena replied: "Stop it. You need to listen to Scooter [Braun, his manager] and go to rehab. U r sick."
The Baby singer - who is being investigated by police over an egging attack on his neighbour's home - then sent another explicit photograph and wrote: "Rehab? Fuck that! I make that fucker so much money."
Upon receiving the picture, Selena told the star they are "done" and suggested his friend Lil Za - who was arrested last week for drug possession following a police raid on Justin's home over the egging attack - had "taken the fall" for his behaviour.
She wrote: "And how can u let [Lil Za] take the fall or your actions. U need to grow the fuck up. I hope you get jail time. U deserve it at this point."
Drugs and drug paraphernalia
After the 21-year-old starlet also advised the Never Say Never star to "retire", he appeared to see red and launched a foul-mouthed attack on her.
He wrote: "FUCK YOU!!!!! I need to grow up?! HA ok! Enjoy life with OUT ME Bitch!!! Fuck you. Fuck Scooter. Fuck all y'all. IAM DONE!
"Can't hear you over my cash, babe! You're only famous cuz of me. You know it. I know. Everybody knows. Bye ... Go fuck someone else. Keep that talentless pussy away from me!"
Meanwhile, it has been claimed there were drugs and drug paraphernalia - including two large cookie jars filled with marijuana - "strewn all over" Justin's mansion when police raided the property.
According to gossip website TMZ, the star also has a "dedicated smoking room" in his house.
However, police didn't seize any of the items because they were primarily looking for video equipment and it is likely a search of jars and other items would have exceeded the remit of their search warrant.