After an 18-month investigation, the Union County Sheriff's Office has arrested more than a dozen people in a drug round-up.

After an 18-month investigation, the Union County Sheriff's Office has arrested more than a dozen people in a drug round-up.

At 6:30 a.m. Wednesday, deputies executed arrest warrants for 18 adults and an 17-year-old girl on drug charges.

Lt. Jamie Patton of the sheriff's office said "two confidential sources" led to the arrests.

Sheriff's office spokesperson Sgt. Chris Skinner said the investigation involves more than 37 purchases of illicit drugs, including heroin, marijuana, cocaine, OxyContin, ecstasy and crack cocaine. He said the investigation is expected to involve more than 75 felony counts of drug-related crimes.

Patton said nearly half the arrests involve heroin. Union County Prosecutor David Phillips earlier said heroin abuse is a rising problem in Union County, saying Mexican gangs from Columbus bring it in.

Patton said 12 adults and the 17-year-old girl were in custody at press time. Two of those adults already were serving time at the Pickaway Correctional Institution for other crimes. Suspects include residents from Marysville, Milford Center, Richwood, Ostrander, Springfield and Grove City.

As of press time, the following adults were in custody: Phyllis C. Barta, 53, 991 Coventry Place, Apt B; Marysville; Mardean F. Keller, 38, 20215 state Route 347, Raymond; Clarence J. Erwin, 48, 47 Spruce Drive, Marysville; Joshua Andrew Lutz, 20, 144 Beatty Ave., Richwood; Perry R. Howell, 35, 23755 Rapp Dean Road, Raymond; William Joseph O'Neil, 21, 17780 Timber Lane, Marysville; Jonathan L. Troyer, 26, 287 Redwood Drive, Marysville; George L. Cook, 33, 17820 Bear Swamp Road, Marysville; Crystal A. Wallace, 23, 17820 Bear Swamp Road, Marysville; David. R. Giles, 26, 130 W. 3rd St., Marysville; James T. McCarty, 23 and Kenneth E. Czarnecki, 40, have addresses listed at the Pickaway Correctional Institute, 11781 state Route 762, Orient.

While the sheriff's office handled the investigation, other law enforcement agencies assisted in the arrests, including Hilliard, Springfield and the Drug Enforcement Agency in Columbus.

Phillips said some of the 19 suspects acted in concert while others acted independently of each other.

Phillips said drugs are a serious problem in Union County.

"In my experience in this office, I'd say a good percentage of the cases we prosecute here are drug-related," he said. He said this includes burglaries and thefts stemming from an addict looking to buy drugs.

Patton said the last high-profile roundup in Union County occurred in April of 2005 during the CLEAN operation, a joint effort of the Marysville police department and the Union County Sheriff's office. He said CLEAN is an acronym for "citizens and law enforcement against narcotics." The operation led to a Union County grand jury returning 211 felony counts against 42 defendants.

Drug round-ups will happen "as often as necessary," Phillips said. "Sometimes it's a matter of resources."