BILLINGS, Mont. (AP) — Authorities are charging a Billings man with two home-invasion rapes.

Billings Police Chief Rich St. John and Yellowstone County Attorney Scott Twito said Monday 41-year-old Toby Eugene Griego was arrested last week.

He was to be charged in Justice Court Monday with at least 28 criminal counts involving the sexual assault of two Billings women on May 27 and July 2.

Authorities say he is a suspect in four other attacks dating back to January.

Twito says a tip led authorities to Griego.

Charging documents say Griego has prior convictions in New Mexico, including a 1997 abduction and rape of a 16-year-old girl in Sante Fe.

Griego has lived in Billings since 2008.

It was not immediately clear if he had an attorney.