According to a jail spokesperson, Hopper's bail is set at $25,000.
In a shocking mugshot, the normally clean-cut 24-year-old appears haggard and unkempt.
A spokesman for the Nebraska State Patrol told Radar Hopper was arrested at 3:45 PM after a Nebraska State Patrol trooper stopped his vehicle for failure to signal.
"During the traffic stop, the trooper detected drug activity and searched the vehicle," Officer Cody Thompson told Radar. "Troopers found 14g of marijuana, 4 amphetamine pills, and 3g of psilocybin mushrooms."
Hopper was in the car with 26-year-old actress girlfriend Uma Von Wittkamp, who was also arrested on drug possession charges.
Hopper was charged with possession one ounce of marijuana and for possession of a controlled substance (psilocybin). Psilocybin is also referred to as mushrooms, a psychedelic drug.
Von Wittkamp was charged for possession of amphetamine and psilocybin.
Hopper has spoken publicly about his struggle with substance abuse in the past. In an interview with E5, he admitted he fell in with the "wrong crowd" following his famous parents' nasty divorce.
"I was doing a lot of stuff, but meth was the main one that brought me down. I went to rehab because I woke up in hospital and my dad said, 'Rehab? Or bus bench?' I was like, 'I'll take the bed,'" Hopper said.
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