A federal agency and five conservation groups have put together a reward totaling $15,500 for information on the illegal killing of an Oregon wolf in Klamath County.

The wolf, OR-33, died of gunshot wounds in late April but the case wasn’t confirmed until October following tests on the wolf’s DNA.

It is a violation of the federal Endangered Species Act to kill a gray wolf in the western two-thirds of Oregon, along with a violation of Oregon state game laws.

The wolf's carcass was found about 20 miles northwest of Klamath Falls in Fremont-Winema National Forest, U.S. Fish and Wildlife Service officials said.

More:ODFW biologists fit daughter of famous OR-7 gray wolf with GPS collar

The federal agency and Oregon State Police offered a $5,000 reward for information leading to the arrest and conviction of OR-33′s killers.

Five conservation groups bolstered that total by $10,500 Tuesday.

“This is a heartbreaking loss for Oregon’s wolves,” said Amaroq Weiss, West Coast wolf advocate at the Center for Biological Diversity, one of the groups that contributed money.

“Wolf recovery in Oregon depends on wolves like OR-33 making their way west and thriving, so his death is a major setback. We hope someone will do the right thing and come forward with information.”

OR-33 was a 4-year-old male gray wolf that dispersed from northeast Oregon's Imnaha Pack to southwest Oregon, where he became well-known.

Previously:Collared wolf OR-33 shot dead northwest of Klamath Falls

In 2016, OR-33 roamed almost within Ashland city limits — a city of more than 20,000. From June 10-12, he attacked and killed two goats and one lamb at a small livestock operation northeast of Ashland, according to USFWS.

He was seen by multiple residents, and his photo was captured by a hunter’s trail camera near Emigrant Reservoir, about 6 miles southeast of Ashland.

“This wolf is acting like David Lee Roth,” said Greg Roberts, a media personality in Southern Oregon said at the time. “I’ve had eight people in Ashland say that they’ve seen him around their property.”

At least eight wolves have been poached or died under mysterious circumstances in Oregon since 2015, the conservation groups said.

“Poaching is an acute problem in Oregon, which demands serious attention from lawmakers and wildlife management officials to strengthen and enforce wildlife laws, and to deter and fully prosecute criminals,” a news release from the groups said.

Zach Urness has been an outdoors writer, photographer and videographer in Oregon for nine years. He can be reached at zurness@StatesmanJournal.com or (503) 399-6801. Find him on Twitter at @ZachsORoutdoors.