Cecil's 'brother' believed alive despite reports

Reports that Jericho, an ally (previously, but mistakenly, reported as the sibling) of Cecil the lion whose death sparked global outrage, had also been killed were denied by researchers, as it emerged the American hunter who admitted he killed a popular lion in Zimbabwe is in touch with federal authorities.

Piper Hoppe, 10, from Minnetonka, Minnesota, holds a sign at the doorway of River Bluff Dental in Bloomington, Minnesota, on July 29, 2015, during a protest against Cecil's killing.
Eric Miller | Reuters

A representative for the Minnesota dentist accused of illegally killing the lion nicknamed Cecil reached out to the U.S. Fish and Wildlife Service late Thursday afternoon, after the agency said attempts to reach him had failed.

The case has sparked international outrage, and has trended for days on social media.

"Late yesterday afternoon, the U.S. Fish and Wildlife Service Office of Law Enforcement was contacted by a representative of Dr. Walter Palmer," according to a statement sent to CNBC on Friday. "The service's investigation is ongoing and appreciates that Dr. Palmer's representative voluntarily reached out to the service."

On Saturday, Zimbabwean officials said in a statement that Jericho was believed to have been taken out during an illegal hunting operation in Hwange National Park. This has since been denied by researchers tracking Jericho to Reuters and The Guardian.

In a statement posted on Facebook, Zimbabwe's Conservation Task Force Chairman Johnny Rodrigues said "it is with great sadness and regret that we report that Jericho was shot dead at 4pm this afternoon. We are absolutely heartbroken," Rodrigues said, adding that more information will be released soon.

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However, Brent Stapelkamp,a researcher monitoring the pride via GPS tag, told Reuters: "He looks alive and well to me as far as I can tell."

The U.S. Fish and Wildlife Service told CNBC on Thursday that Palmer had not responded to attempts to contact him. Attempts by CNBC since Wednesday to contact Palmer for a comment have resulted in no response.

Palmer became the subject of international attention—and the target of widespread anger—when it was revealed that he had killed and beheaded an adult male lion near a national park in Zimbabwe.

The animal wore a GPS collar because it was part of an ongoing study sponsored by Oxford University. Zimbabwean authorities have already arrested Palmer's hunting guide and the owner of the land where the lion was shot, after details suggested the hunt was illegal.

--CNBC's Javier E. David and Reuters contributed to this article.