An alert drug dog helped authorities nab a man carrying almost three grams of methamphetamine Tuesday night.

Scott Mark Spencer, 52, of De Leon, was arrested and charged with possession of a controlled substance during what started as a routine traffic stop on West Washington Street, according to Captain Jason King with the Stephenville Police Department.

King said shortly before 7 p.m., Officer Curtis Dees stopped Spencer, who was driving a 2005 Toyota Corolla, at Food Plaza for changing lanes without using a signal. That's when Bo, the K-9 unit traveling with Dees, alerted on both the vehicle and Spencer.

“Officer Dees then found the drugs inside a cigarette box in Spencer's shirt pocket,” King said.

Spencer, who has a “lengthy criminal history,” according to King, was arrested and taken to the Erath County Jail. He is being held on a $10,000 bond.

“We suspect that Spencer was in Stephenville trying to sell the drugs,” King said.

SARA VANDEN BERGE is Managing Editor of the Empire-Tribune. She can be reached at 254-968-2379, ext. 240.