BLOOMINGTON, Minn. (WCCO) — The Twin Cities trophy hunter at the center of worldwide protest over a lion’s killing is now being sought by the U.S. Fish and Wildlife Service.

The agency said Thursday that it has been unable to reach Dr. Walter Palmer despite repeated attempts to contact him.

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The Bloomington dentist was identified on Tuesday as the American hunter who killed a popular lion named Cecil in Africa.

According to a statement by Palmer, he regrets the killing because he didn’t know it was a research animal.

Game officials in Zimbabwe say Palmer’s professional hunting guide lured the animal with a scent trail to private land outside a protected national park where Palmer shot it with a crossbow.

There’s still no sign of Palmer, two days after he issued a written statement acknowledging his role in the lion’s death. He reportedly paid $55,000 for the license and guided trip to Zimbabwe.

For the third straight day, his Bloomington dental practice remained closed.

Outside the office, Saleem Husain said, “I don’t think he’ll get into any legal trouble because the guides will take more of the hit. Obviously, I think it’s more of a moral issue.”

Zimbabwe authorities have charged his hunting guide, Theo Bronkhorst, for killing the lion without a quota permit.

Now, Palmer is being sought for questioning by the U.S. Fish and Wildlife Service in Minnesota.

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Thursday, the USFWS sent out a tweet, saying investigators will go to where the facts lead. The tweet also asked for Palmer or his representative to contact investigators immediately.

Legal authorities say it’s doubtful Palmer violated any U.S. laws since the lion’s head and cape were confiscated in Africa and never made it to the U.S.

At the United Nations in New York on Thursday, the General Assembly passed a resolution urging countries to crack down on poaching.

Afterwards, the German ambassador to the UN said, “hunting activities are partly legal and partly illegal. This resolution fights all illegal aspects.”

Meantime, police in Bloomington and Eden Prairie are keeping close tabs on Palmer’s dental office and home as the protests over the lion’s death continue.

Late Thursday, the Telegraph, the London newspaper that broke the story interviewed Palmer’s guide, Theo Bronkhorst, who said the hunt went wrong from the very beginning.

He said neither man saw the collar until the lion was recovered 40 hours later and that when they did, both men were devastated.

According to the Telegraph story, instead of hiding the collar in a tree Bronkhorst said they should have turned the collar over immediately.

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Yet even after the lion hunt went bad, the guide said that Palmer asked Bronkhorst if he would find him a large elephant to hunt.