LOS ANGELES (CBSLA.com) — There’s growing outrage across the world over the killing of a protected lion in Zimbabwe.

The man at the center of the controversy is dentist and trophy hunter Walter Palmer, who paid at least $50,000 for the hunt where he killed “Cecil” the lion, according to the Zimbabwe Conservation Task Force.

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Police are now monitoring Palmer’s Bloomington office, which was closed this week amid reports that the dentist has received death threats online.

Outside the dental clinic, people have been leaving signs and stuffed animals as a memorial for the beloved animal, known for his distinctive black mane.

(credit: Adam Bettcher/Getty Images)

(credit: Adam Bettcher/Getty Images)

And the rest of the world is taking notice. Cecil’s death has made international headlines and was among the top trending stories on Facebook and Twitter this Tuesday and Wednesday.

Late-night TV host Jimmy Kimmel choked up while discussing Cecil’s killing during his broadcast Tuesday night and called it a “disgusting tragedy.” He urged people to donate to the wildlife preservation group who had previously been keeping track of the lion, by visiting wildcru.org.

Celebrities are expressing their shared disgust on Twitter.

The backlash is to news this week that Cecil was lured away from a sanctuary, killed, beheaded and skinned.

On July 1, professional Zimbabwean hunter Theo Bronkhorst and local landowner Honest Zdlovu escorted Palmer on a nighttime hunt where they tied a dead animal to the back of a truck to bait the lion, the task force reports.

(credit: Zinyange Auntony/AFP/Getty Images)

(credit: Zinyange Auntony/AFP/Getty Images)

Palmer reportedly shot Cecil with a crossbow, then followed the injured lion for 40 hours before someone from his group finished him off with a gun.

The 13-year-old animal was outfitted with a collar and tracking device by an Oxford University research team. Officials were able to use the collar, which the hunters reportedly had tried to destroy, to find the suspects.

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Palmer says he thought everything about the trip was legal and that he wasn’t aware the lion was well-known until the end of the hunt.

The dentist released a statement that said, in part: “I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion.”

Bronkhorst and Zdlovu appeared in court Wednesday on poaching charges. If convicted, both men face up to 15 years in prison.

“The Birds” actress Tippi Hedren, a known animal activist, spoke Wednesday to CBS2’s Jeff Nguyen.

Hedren also runs a wild animal sanctuary, the Shambala Preserve, in Acton.

“I am so far on the side of this man being punished severely. He should end up in jail forever,” Hedren said.

She is happy to see the world outrage about the killing.

“I think it’s wonderful they’re lashing out at him. He deserves it. He had no right to kill that animal,” she said.

Hedren founded the Shambala Preserve in 1983.

The sanctuary has rescued approximately 250 tigers and lions born in captivity in the United States.

She told Nguyen the phrase “trophy hunting” makes her cringe.

“I don’t understand how anybody can go out and look those animals in the eyes and take a weapon and put those lights away,” she said.

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Hedren said when she first started the sanctuary there were around 20,000 lions in Africa. That number, she says, has dwindled to less than 5,000.