Cecil the Lion's Killer, Dr. Walter Palmer, Contacts Authorities

Dr. Walter James Palmer, the American dentist who sparked outrage after killing Cecil the lion in Zimbabwe, has reached out to U.S. authorities, U.S. Fish and Wildlife officials said Friday.

A representative for Palmer "voluntarily" reached out to the U.S. Fish and Wildlife Service Office of Law Enforcement on Thursday, the service said in a statement. 

On Thursday, officials had said efforts to contact Palmer had been unsuccessful and urged him on Twitter to get in touch.

Palmer has not been charged with a crime and has said he trusted his local guides to obtain necessary wildlife hunting permits. 

In Zimbabwe, the illegal killing of a lion is punishable by a fine of $20,000 and up to a decade behind bars, and Zimbabwe's environment, water and climate minister said Friday that officials would appeal for the extradition of Palmer, who has since returned to the U.S.

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