ANACONDA, Mont. (AP) — Authorities in southwestern Montana say Anaconda-Deer Lodge County Commissioner Robert Pierce has been arrested on suspicion of felony sexual intercourse without consent and sexual assault against a minor.

Authorities tell the Missoulian that Pierce was taken into custody Friday and released from jail after posting $20,000 bond.

Police Chief Tom Barkell says the arrest followed a six-month investigation by the state Department of Justice Division of Criminal Investigation.

A phone number listed for Pierce on the county's website had been disconnected and he could not be reached.