(CNN) -- An Ohio sheriff defended the killings of more than four dozen lions, tigers and other wild animals Wednesday after they were turned loose from a farm outside Zanesville by its suicidal owner.
Of the 56 animals released Tuesday night, only a grizzly bear, two monkeys and three leopards were taken alive, Muskingum County Sheriff Matt Lutz said. One monkey remained unaccounted for Wednesday night, but Lutz and conservationist Jack Hanna, who assisted in the effort, said the animal may have been eaten by one of the big cats.
Lutz told reporters earlier that the farm's owner, Terry Thompson, pried open cages and left the farm's fences open before dying from a self-inflicted gunshot wound Tuesday afternoon. Lutz told CNN's "Anderson Cooper 360" that none of his deputies are equipped with tranquilizer guns. And with night falling Tuesday, he gave the order to kill the escaped animals.
"If this had been a 9 o'clock or 10 o'clock incident, in the middle of the day, odds are high that we may have been able to surround the area and keep everything contained," he said. "But our biggest problem that we had was nightfall. We had about an hour, hour and a half of light, and we just couldn't take the chance."
As of Wednesday afternoon, authorities had killed 49 animals -- 18 tigers, 17 lions, six black bears, two grizzly bears, three mountain lions, two wolves and a baboon. Those captured alive were taken to the Columbus Zoo.
Hanna, the zoo's director emeritus, said he was upset by loss of "precious" animals, but defended the decision to use deadly force.
"To have no one hurt or killed here with 40-something animals getting loose is unbelievable," he told CNN's "The Situation Room."
Hanna led a team of experts who arrived with four tranquilizer guns late Tuesday in an effort to corral the animals. He said the drugs take several minutes to subdue an animal even with a good shot, and one tiger had to be killed Wednesday afternoon when it turned on a veterinarian after being hit with a tranquilizer dart.
Overnight, sheriff's deputies searched the eastern Ohio woods around Zanesville with night-vision gear and patrolled in pickups, armed with shotguns. Flashing signs on the highways in eastern Ohio warned motorists Wednesday: "Caution. Exotic animals." Schools were closed, and some frightened residents said they were keeping to their homes as sheriff's deputies hunted lions, tigers, leopards and grizzly bears.
"Yeah, there's a lion on Mount Perry Road. ... I just drove by and it walked out in front of me and was standing there under the street light," one caller to 911 told deputies.
Zanesville Mayor Howard Zwelling said he received calls from people who were concerned that the animals had been killed. He said authorities were trying to use tranquilizers whenever possible. But Lutz told reporters, "We are not talking about your normal everyday house cat or dog.
"These are 300-pound Bengal tigers that we have had to put down," he said.
Thompson's property is about 2 miles outside Zanesville. The 62-year-old had been released from a federal prison September 30 after pleading guilty earlier this year to possessing illegal firearms, including five fully automatic firearms. A civil case seeking forfeiture of firearms was pending, according to the U.S. attorney's office in Ohio's Southern District.
He also had been convicted of animal cruelty and animals at large in 2005 and was arrested several times for traffic violations.
Authorities were waiting on the results of an autopsy to determine the exact cause of his death, but Lutz said Thompson shot himself just after releasing the animals.
Sam Kopchak, Thompson's neighbor, said he saw lions and bears running free Tuesday evening, with one tiger chasing horses. Kopchak managed to get himself and his horse into his barn and telephoned his mother.
"We have a major problem,:" he told her. That's when she called the police.
"It was like a war zone," Kopchak said when authorities descended on Thompson's property, set off the road named after Kopchak's family.
Kopchak described Thompson as aloof. He loved animals. Kopchak saw him driving one time with a baby black bear on his chest.
Lutz said authorities found primates inside the house.
The community was in a state of "shock and surprise," said Tom Warne, owner of Donald's Donuts and a lifelong resident of Zanesville.
"It's the craziest sort of thing," he said.
Warne said he had met Thompson a few times. He used to come into the doughnut shop at one time.
The Humane Society of the United States and the American Society for the Prevention of Cruelty to Animals urged Ohio officials Wednesday to issue an emergency rule to crack down on exotic animal ownership in the wake of the slaughter. A previous emergency order issued by then-Gov. Ted Strickland that prohibited people convicted of animal cruelty from owning exotic animals expired in April.
The Humane Society said Thompson "would almost certainly have had his animals removed by May 1, 2011, if the emergency order had not expired."
"Every month brings a new, bizarre, almost surreal incident involving privately held, dangerous wild animals," said Wayne Pacelle, president and CEO of the Humane Society. "In recent years, Ohioans have died and suffered injuries because the state hasn't stopped private citizens from keeping dangerous wild animals as pets or as roadside attractions. Owners of large, exotic animals are a menace to society, and it's time for the delaying on the rule-making to end."
Fritz Douthitt, a volunteer at the Zanesville Animal Shelter Society, recalled Thompson's 2005 trial for cruelty and torture of cattle and bison. She said he had not been able to get up the hill to feed his livestock, and they died.
Douthitt said it is inappropriate for people like Thompson to keep dangerous animals as pets, just as it was to shoot so many of them. Local governments, she said, ought to train law enforcement officers so they are prepared for bizarre cases such as the one that unfolded in Zanesville.
For lions, tigers and bears to die, she said, was "unforgivable."
CNN's Jordana Ossad, Andy Rose, Jason Carroll, Ninette Sosa, Ed Payne and Maggie Schneider contributed to this report.