Six more arrests have been made in connection with warrants served by several police agencies Nov. 19.

Detective Lt. Jonathon Simpson of the Madison Police Department said Tuesday that Brad Randall, 30, of Madison, and Jonathan Thompson, 21, of Madison, were both arrested by the Madison Police Department on warrants for dealing controlled substances.

James Amburgey, 28, of Madison, was served by the Boonville Police Department, and Dustin Griffin, 30, of Madison, was arrested by the Terre Haute Police Department. Both have been transported to the Jefferson County Jail.

Indianapolis Metro Police arrested Eric Smith and Jamie Andrews. Simpson said Smith and Andrews are still being held at the Marion County Jail.

Warrants were issued after a year-long investigation into drug activity in Madison. Last week, authorities arrested 20 Hanover and Madison residents in connection with the same case.

Randall was wanted on three separate warrants, including two counts of dealing a controlled substance and one count of conspiracy to deal a controlled substance and a probation violation, according to the Madison Police Department.

Thompson was arrested on a warrant for suspicion of dealing marijuana.

Griffin faces a charge of dealing a controlled substance, while Amburgey faces charges of dealing a controlled substance and conspiracy to deal a controlled substance.

The case is still under investigation.