Theo Bronchorst, a professional hunter, and Honest Trymore Ndlovu, a landowner, both Zimbabweans, said through their attorney that they were innocent of poaching charges, which officials said could bring a sentence of 10 years in prison.
Zimbabwean authorities said that Walter J. Palmer, a dentist from Minnesota, paid at least $50,000 for the hunt. Palmer has said he relied on the expertise of local guides "to ensure a legal hunt."
But the lion that he and his local guides killed wasn't just any lion, according to Zimbabwean officials.
The 13-year-old lion, recognizable by the black streaks in his mane, suffered a slow death
, according to the Zimbabwe Conservation Task Force
The hunters lured him out of the sanctuary of the park with a dead animal on top of a vehicle, the conservation group said.
Palmer, officials said, then shot the lion with a crossbow, a method for which he is known. But Cecil survived another 40 hours until the hunters tracked him down and shot him with a gun.
Cecil was skinned and beheaded, and the hunters tried to destroy the GPS collar that Cecil was wearing as part of research backed by Oxford University, the group said.
"I had no idea that the lion I took was a known, local favorite, was collared and part of a study until the end of the hunt," Palmer said Tuesday in a statement. "I relied on the expertise of my local professional guides to ensure a legal hunt."
Torrent of anger online
His alleged role in Cecil's death brought a wave of online anger crashing down on him
The Yelp page
for his dental practice in Bloomington, Minnesota, was inundated with reviews posted by people irate over his lion hunting.
"Shame on you, killing a majestic creature," wrote a user named Charmie P.
The website for Palmer's business, River Bluff Dental, appeared to have been taken down.
A torrent of outrage flowed on social media, with celebrities such as Sharon Osbourne lambasting the dentist.
"I hope that #WalterPalmer loses his home, his practice & his money," Osbourne tweeted. "He has already lost his soul."
Famed primatologist and conservationist Jane Goodall spoke
about Cecil, saying, "He was not even killed outright, but suffered for hours before finally being shot with a bullet. . ... And this behavior is described as a 'sport.'"
"Only one good thing comes out of this," she said. "Thousands of people have read the story and have also been shocked. Their eyes opened to the dark side of human nature. Surely they will now be more prepared to fight for the protection of wild animals and the wild places where they live. Therein lies the hope."
Investigations suggest the killing of Cecil was illegal because the landowner "was not allocated a lion on his hunting quota for 2015," said a statement from the Zimbabwe Parks and Wildlife Management Authority
and Safari Operators Association of Zimbabwe
In an email obtained by CNN affiliate WCCO, Palmer wrote a letter to his patients, saying, "I deeply regret that my pursuit of an activity I love and practice responsibly and legally resulted in the taking of this lion. That was never my intention."
Palmer said that the media, along with "a substantial number of comments and calls from people who are angered by this situation and by the practice of hunting in general," has disrupted his ability to see his patients.
"I apologize profoundly for this inconvenience and promise you that we will do our best to resume normal operations as soon as possible."
Dentist's enthusiasm for hunting with bow and arrow
Cecil's killing doesn't appear to be the first time Palmer has gotten into trouble while hunting.
A man by the same name and age, and from the same town, illegally killed a black bear in Wisconsin several years ago, according to court documents.
That individual pleaded guilty to making false statements knowingly to the U.S. Fish and Wildlife Service, and was sentenced to one year on probation and ordered to pay a fine of nearly $3,000, records show.
A New York Times article in 2009
that profiled Palmer and his hunting methods said he had served a year of probation over the false statements case.
The Times article detailed Palmer's skill and enthusiasm for using archery rather than firearms to slay animals.
He is "said to be capable of skewering a playing card from 100 yards with his compound bow," it said, recounting his killing of a large elk with an arrow in Northern California.
Fears for Cecil's cubs
Cecil's death is likely to have a damaging effect on his pride, officials said.
"The saddest part of all is that, now that Cecil is dead, the next lion in the hierarchy, Jericho will most likely kill all Cecil's cubs so that he can insert his own bloodline into the females," the Zimbabwe Conservation Force said.
"This is standard procedure for lions," it warned.
Compounding the problem, "the females of the pride could die trying to defend those young," said Jeff Flocken, the North American regional director for the International Fund for Animal Welfare.
Calls for trophy hunting ban
The killing of Cecil has renewed calls among activists for a ban on trophy hunting of animals such as lions in Africa.
By early Wednesday, more than 210,000 people signed an online petition
demanding "justice" for Cecil. The petition called on Zimbabwean President Robert Mugabe to stop issuing hunting permits to kill endangered animals.
African lion populations have fallen almost 60% over three decades, and as few as 32,000 of them remain in the wild, according to the International Fund for Animal Welfare.
Hunters argue that by paying big bucks to hunt specific animals with authorities' permission, they can help fund the preservation of endangered species.
That's the argument put forward by Corey Knowlton, a Texan who paid $350,000 to hunt and kill a black rhino in Namibia
earlier this year.
Researchers studied effects of hunting on Cecil's park
But many conservationists dispute the value of that approach.
"Studies have shown that with these big, lavish hunts, only 3% to 5% of the income from that hunt actually ends up for local people on the ground where the hunt happens," Flocken said.
"There are much better ways to earn this kind of money -- revenue from nature tourism, where the animal's not killed, brings in three to 15 times what's brought in from these trophy hunts in Africa," he said.
The Oxford University researchers who have studied the lions where Cecil lived found that trophy hunting just outside the national park had "an alarming impact on lion numbers and population structure within the park."
"Each removal of a male lion by hunters on the borders of the park created a 'territorial vacuum' which drew males from further inside the protected area into boundary areas, where they, too, became vulnerable to hunters," the university said
A complete moratorium on trophy hunting around the park between 2005 and 2008 coincided with a 50% increase in the lion population there, the researchers noted.
Trophy hunting restarted in 2009 but with close monitoring by the Oxford research team, Zimbabwean authorities and other groups to ensure its impact on the lion population was sustainable.