The Minnesota dentist accused of killing one of Africa's most famous lions reportedly closed his practice

When Minnesota dentist Walter Palmer went on his $55,000 safari to Zimbabwe, he probably did not expect this.

Palmer has been accused of killing Cecil, a beloved 13-year-old lion and is now facing poaching charges.

But the fiercest backlash came from social media where people have been calling for Palmer to be hunted and killed.

The animal rights group PETA called for Palmer to be hanged and others have said he should be publicly shamed or have his teeth pulled out without anesthetic.

The threats got so bad that they prompted Palmer to close his dental practice. 

Palmer's dental practice Facebook page was taken offline on Tuesday, VICE News reports, as it was receiving too many nasty comments.

Vice notes that people "left stuffed animals at the door to his shuttered office Tuesday in a sign of protest."

Palmer has spoken out saying he was "upset" over the comments and threats he was receiving and still insists he did not know the lion he killed was protected and that he regrets killing the animal.

"I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion," Palmer said in a statement and added that his guides had permits and that he thought everything was handled properly. 

Palmer, who already has a felony record related to shooting a black bear in Wisconsin, according to VICE News, also said he had not been contacted by either US or Zimbabwean authorities. "I have not been contacted by authorities in Zimbabwe or in the U.S. about this situation, but will assist them in any inquiries they may have," Plamer said in his statement.  

One of the most graphic description of what Palmer's punishment should be came from media personality Piers Morgan, who was among the people calling for him to be hunted and killed. 

He also added more graphic details of what he would do:

"I will sell tickets for $50,000 to anyone who wants to come with me and track down fat, greedy, selfish, murderous businessmen like Dr. Palmer in their natural habit. We would all take a bow and fire a few arrows into his limbs to render him incapable of movement.

"Then we'd calmly walk over, skin him alive, cut his head from his neck, and took a bunch of photos of us all grinning inanely at his quivering flesh," Morgan wrote in his column for the Daily Mail.