WASHINGTON - US authorities opened a probe Thursday into the killing of a beloved lion in Zimbabwe, as the American doctor who hunted the big cat remained in hiding amid mounting global outrage.
Rachel Augusta leads a protest against the killing of Cecil the lion in the parking lot of hunter Dr. Walter Palmer's River Bluff Dental Clinic on July 29, 2015 in Bloomington, Minnesota
Trophy hunter Walter Palmer killed Cecil the lion earlier this month after the feline was allegedly lured out of the Hwange National Park boundaries.
The professional Zimbabwean hunter who organized the hunt has been charged in Zimbabwe with "failing to prevent an illegal hunt." But a court hearing for the landowner accused of allowing the hunt was delayed on Thursday.
The US Fish and Wildlife Service said it had opened a probe into the hunt.
"We're investigating the killing of #CecilTheLion. Will go where facts lead. We ask Dr. Palmer or his rep to contact USFWS immediately," the agency said on Twitter.
But Palmer remained out of the public eye, as crowds left plush toys of lions, tigers and monkeys at his River Bluff Dental practice in Minnesota.
A sign reading "Rot in Hell" was plastered on the office door.
A Minnesota congresswoman joined calls to investigate the dentist, a seasoned hunter with a poaching conviction over the 2008 killing of a black bear in the United States.
"To bait and kill a threatened animal, like this African lion, for sport cannot be called hunting, but rather a disgraceful display of callous cruelty," Betty McCollum said Wednesday.
She urged the US Attorney's Office and the USFWS to "investigate whether US laws were violated related to conspiracy, bribery of foreign officials, and the illegal hunting of a protected species or animal."
Meanwhile, Safari Club International, an international hunting organization that Palmer belonged to, said it also supported a probe and that it had revoked his membership.
"SCI has imposed immediate emergency membership suspensions of both the involved hunter and his guide/professional hunter, and they will remain in place pending the outcome of an investigation," the group said in a statement.
Cecil was a popular attraction among many international visitors to the Hwange National Park and was part of a University of Oxford research project.
The beloved lion was apparently enticed to leave the park's boundaries by bait and initially shot with a bow and arrow before Palmer and his guide tracked Cecil down and shot him dead with a gun some 40 hours later.
On Tuesday, Palmer issued a statement expressing regret at killing Cecil but said he had no idea the lion was protected and part of a study and that he thought the hunt was legal.
Twitter was aflutter with insults aimed at the wealthy dentist, and the hashtag #WalterPalmer was trending.
Rocker Ozzy Osborne's wife, Sharon, joined the online attack.
"#WalterPalmer is Satan. I don't know how anyone could go to this man for dental services after this. He is a killer. Beware!," she wrote.