GREEN RIVER, WYOMING -- A former Bureau of Land Management worker arrested last week in connection with the shooting deaths of three horses at a holding facility in Rock Springs in June is facing seven felony and misdemeanor counts, according to authorities.

Jason Edward Hein, 39, was arrested in Billings, Montana on Thursday by deputy sheriffs of the Yellowstone County [Mont.] Sheriff's Office and BLM law enforcement officers.

Sweetwater County authorities said Wednesday that the results of a joint county and federal investigation were turned over the county attorney's office, which filed charges against Hein in Circuit Court in Rock Springs.

Authorities said investigators uncovered evidence allegedly implicating Hein and recovered the .22 caliber rifle used in the shooting.

Hein was charged with three counts of felony aggravated cruelty to animals, one misdemeanor count of unlawful killing of wild horses, and two felony counts and one misdemeanor count of property destruction and defacement.

Two BLM personnel arriving for work on June 12 discovered that three horses had been shot and killed sometime during the night of June 11 at the BLM's Rock Springs corrals.

The horse carcasses had been dumped in the holding facility's upper storage yard.  Two of the horses killed were privately owned, and a third was a wild mustang that was being held at the corrals. The wild horse had been gathered as part of BLM roundup operations and was being held at the Rock Springs facility while up for adoption.

Hein was employed as a maintenance worker at the Rock Springs holding facility at the time of the shootings. BLM officials said Hein was on administrative leave from the BLM's Rock Springs Field Office when he was arrested in Billings.

Sweetwater County Sheriff Rich Haskell said county and BLM investigators processed the crime scene at the corrals and recovered, among other evidence, a number of expended .22 Magnum cartridge cases.

Analysis at the Wyoming State Veterinary Laboratory in Laramie determined the horses' demise was the result of gunshot wounds that caused "penetrating trauma."

Haskell said the bullet fragments and cartridge cases found at the scene were examined at a federal forensic laboratory and were matched to a .22 Magnum rifle recovered from the BLM firearms locker at the holding facility.

Hein is free on a $50,000 bond set in Justice Court in Billings on Friday.

Haskell said Hein has waived extradition and authorities were working to facilitate his return to face charges in Sweetwater County.