Authorities in Upshur County have uncovered what they say is the largest meth manufacturing operation seen in East Texas in more than 15 years. At around 10:00 pm Saturday night, Sheriff Deputies were called to a home on FM 49, just West of Gilmer. There they found more than 400 grams of methamphetamine, 3/4 of a gallon of pure meth oil valued at $70,000, and numerous rooms full of manufacturing equipment. They also arrested 32-year-old Greg Russell and charged him with possession of meth and manufacturing of meth. Russell remains in the Upshur County Jail tonight on two separate $100,000 bonds. Drug Enforcement Agents from Dallas and Tyler assisted in the bust along with an environmental clean-up team out of Texarkana.