By Douglas Hyde and Steve Almasy, CNN
(CNN) -- Chris Kelly, one-half of the 1990s rap duo Kris Kross, died Wednesday at an Atlanta hospital after he was found unresponsive at his home. He was 34.
How Kelly died isn't known, and the Fulton County Medical Examiner's Office said an autopsy is planned for Thursday.
Kelly, together with Chris Smith, shot to stardom in 1992 with "Jump," which spent eight weeks on top of the Billboard Hot 100.
The duo opened for Michael Jackson that year on his Dangerous World Tour.
And their penchant for wearing their clothes backward were, at least for a time, widely emulated.
"I'm wearing my clothes to work backwards tomorrow," Michael Skolnik, editor in chief of the hip hop site Global Grind said, when he learned of the death.
Leslie Tookes, a CNN project coordinator, lived next door to Kelly. Like others, she too was saddened by his untimely death.
"We often heard him playing classical music and the piano," Tookes said. "He was a low-key type of person who was very talented and courteous, friendly and wonderful to our 5-year-old twins.
"Indeed, gone too soon."
Discovered at a mall
Kelly and Smith were 13-year-olds when they were discovered in 1991 at an Atlanta mall by producer Jermaine Dupri.
Going by the stage name Mac Daddy (with Smith known as Daddy Mac), the pair followed up their smash "Jump" with the single "Warm It Up."
Together, the songs pushed their debut album, "Totally Krossed Out," to multiplatinum status.
Next came 1993's "Da Bomb."
But the album failed to find the following of the duo's debut, in large part because the boys had hit puberty and they were marketed with a tougher image.
Their career never again reached the heights of their debut, but they continued to make music.
In 1996, the duo released the album "Young, Rich and Dangerous."
The pair reunited for one night in February for a 20th anniversary party for Dupri's So So Def label.
Rapper Da Brat, who also performed that night, wrote about Kelly's death, " REST IN PEACE TO MY LIL BRO CHRIS KELLY OF KRIS KROSS. Dam wasn't we JUST at rehearsal and doin a So So Def20 show?"