U.S. Attorney's Office, District of N.H.

Two New Hampshire men have pleaded guilty to trafficking a huge amount of synthetic cannabis, also called spice, valued at about $4 million.

One year ago, undercover officers traced spice being sold in convenience stores in Hooksett and Londonderry back to two men producing the stuff at three locations in New Hampshire and Massachusetts. Officers found 3,000 pounds of spice, scales, boxes of empty packages, and residue of a controlled substance called AB-FUBINACA.

After pleading guilty, defendants Kyle Hurley, 32, and Robert Costello, 71, could face decades in prison.