Dentist Walter Palmer in contact with authorities over killing Cecil the lion

The U.S. Fish and Wildlife Service is in contact with the man who killed Cecil the lion, according to a statement issued Friday from the federal agency.

A representative for hunter Walter Palmer voluntarily reached out to the Service Thursday, the statement said. Palmer, a Minnesota dentist, had not been heard from since Tuesday when he issued a statement to his patients and closed his dental practice amid protests.

The U.S. Fish and Wildlife Service is investigating the case and the Zimbabwe government has called for Palmer's extradition. Palmer allegedly paid about $50,000 to hunt the animal after it was lured from a national park into an unprotected area.

USA TODAY Network looks at how both countries want to move forward:

What Zimbabwe wants

"We want him tried in Zimbabwe because he violated our laws," Oppah Muchinguri, Zimbabwe's environment minister, said in a news conference Friday. Palmer's use of a crossbow and arrow to hunt Cecil violated Zimbabwe hunting regulations, according to reports.

Zimbabwe officials are appealing to U.S. authorities for help and have begun the extradition process, Muchinguri said.

An extradition treaty does exist between Zimbabwe and the U.S. According to the treaty, an extraditable offense is anything that's considered illegal in both countries and is punishable by more than one year in prison.

Whether or not Palmer can be extradited depends on what Zimbabwe ultimately charges him with, David Glazier, a law professor at Loyola Law School in Los Angeles, Calif., told USA TODAY Network in a phone interview.

"If the offense Zimbabwe charges (Palmer) with also carries a sentence greater than a year in the U.S., then he can be extradited," Glazier said. If Palmer is charged in the U.S. for the same crime, he would not be extradited but would be tried in U.S. courts instead of in Zimbabwe, he said.

That may very well be what happens, according to Glazier.

"It would look to me that the U.S. may have a pretty plausible case to try him," he said.

What the U.S. wants

The U.S. Fish and Wildlife Service is currently on a fact-finding mission and is working to gather as much information as possible. If they conclude the case is worth prosecuting, they will pass it on to the Department of Justice and the DOJ will decide whether to pursue the case.

The African lion is protected under the Convention on International Trade in Endangered Species of Wild Fauna and Flora, an international treaty between 180 countries established in 1975 that works to protect animals and plants. The U.S. Lacey Act was established in 1900 and is the law used to protect both American wildlife and wildlife protected by CITES.

The U.S. Fish and Wildlife Service will likely work to determine whether or not Palmer's hunting trip and the death of Cecil violated CITES.

"The U.S. government looks to me to have pretty robust grounds to prosecute him," Glazier said

At this point, the Service has said it's too early to speculate about what measures, if any, may be taken because the case is still being investigated.
Contributing: Associated Press