Nelly was arrested and charged with simple possession of marijuana, felony possession of drugs and possession of drug paraphernalia in Tennessee, Saturday.
The rapper's bus was pulled over by a state trooper around 9:20 a.m. because it didn't have the required Department of Transportation sticker.
After catching a strong scent of pot, the officer conducted a search and found a baggie of crystal rocks. The rocks tested postive for methamphetamine, TMZ reported.
In addition, the state trooper also found about 100 ziplock bags of drug paraphernalia and a stow of guns - a .50 caliber pistol, a .45 caliber pistol and a .500 magnum Smith and Wesson.
"Nelly was one of several individuals that was on a tour bus that was stopped and searched while traveling through Tennessee," Scott Rosenblum, Nelly's attorney, exclusively told ABC.
"In fact, there had been 15-20 people that had access to the bus prior to the stop. Allegedly, a small quantity of contraband (MDMA aka Molly or Ecstasy) was discovered during the routine search," Rosenblum added.
"We are extremely confident that when the facts come out, Nelly will not be associated with the contraband that was allegedly discovered," he concluded the statement.
While the "Dilemma" singer was booked for possession of methamphetamine, marijuana and drug paraphernalia, his fellow passenger, Brian Jones, was arrested for possession of a firearm.
"The Longest Yard" actor was on his way to his hometown in St. Louis, Mo., when he was arrested and escorted off to the Putnam County Jail, New York Daily News learned.
Despite the charges, the "Just A Dream" singer was released. Putnam County Sherriff's Office said that the hollywood star posted a $10,000 bail.
Nelly started his solo career in 2000. His debut album "Country Grammar" under Universal Records went platinum following its release.
The hip hop singer will be visiting Missouri State University on April 23.
Nelly will be performing, with TLC and New Kids On The Block, at Mandalay Bay Events Center in Las Vegas, Nevada on May 1.
