MTO SHOCK EXCLUSIVE: Hip Hop Superstar Is Reportedly . . . HOOKED ON HEROIN . . . The Veins On His Arm . . . COLLAPSED!!!

Original: just heard a story that HURT OUR HEART - and it's about one of the GREATS from hip hop. We're talking an "A" level rapper from the 2000s era.

According to a TOP SNITCH, one of our favorite rappers (and probably yours too) is hooked on HEROIN.

An insider from the rapper's label told, "[Rapper] is hooked on heroin. He's on it constantly. It's gotten so bad that the veins on his arm collapsed."

How did it happen that one of hip hop's GREATS is now a HEROIN addict? The insider explained, "People don't understand that 'lean' really is just watered down heroin that you drink. After a while you get a tolerance for lean and you need something stronger, like heroin."

And the rapper was KNOWN for carrying lean around in his cup.

The insider added, "He's overdosed a bunch of times [which are] seizures. If he doesn't get into rehab now he's going to die."

Prayers go out to dude.