Federal authorities say a man has been charged with placing booby traps around a Detroit pot-growing operation that hurt another man.

The U.S. attorney's office in Detroit announced Friday that 25-year-old Joshua Ragland was indicted this week on four counts, including manufacturing and possessing destructive devices. He faces up to 40 years in prison if convicted.

The Associated Press left a message seeking comment from his defense attorney, Lisa Dwyer.

Prosecutors say a 29-year-old man walked across a lot in September when he heard explosions and felt pain in his foot. He was treated at a hospital.

Ragland told investigators he was authorized to grow marijuana for medicinal purposes. Michigan voters approved marijuana use for some medical conditions in 2008, but the law conflicts with federal possession and use laws.