He was seen stuffing a marijuana pipe in his backpack at the Hillcrest Park Pavillion.
A 19-year-old Frederick man was arrested for possession of marijuana.
Around 10:30 p.m. Monday night, a Frederick County Police officer saw Matthew Rosenburg in the Hillcrest Park pavillion stuffing a marijuana pipe in his backpack. The officer investigated and found the pipe and more drugs on Rosenburg. He was handcuffed and taken to the Frederick County Adult Detention Center.