Law enforcement officials said Wednesday afternoon that they had accounted for all but one of a menagerie of animals released from a Ohio farm, with a monkey remaining on the loose.

Muskingum County Sheriff Matt Lutz said a missing bear and mountain lion were shot dead and a lion made it to a private backyard, where it died. They were among an estimated 51 exotic animals released Tuesday from Terry Thompson’s farm outside Zanesville. And the Sheriff’s Department said Wednesday afternoon that a wolf, previously unaccounted for, had been killed Tuesday night.

Lutz said preliminary investigations indicated that the 62-year-old Thompson pried open cages and left the farm’s fences open and then died from a self-inflicted gunshot wound. Authorities were waiting on the results of an autopsy to determine the exact cause of death.

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.

Sheriff’s deputies used night vision equipment until daylight Wednesday to continue their search, which was hampered by rain. Lutz said deputies, armed with shotguns, patrolled in pickups. This part of Ohio is wooded and hilly, making it conducive for the animals to hide.

Most of the escaped animals were put down. Lutz called them “senseless killings” of animals that were not in a proper environment.

He said his deputies, who found themselves in a volatile situation, had to shoot some of the animals at close range. A Bengal tiger was killed after it got agitated from a tranquilizer shot.

“We are not talking about your normal everyday house cat or dog,” Lutz said. “These are 300-pound Bengal tigers that we have had to put down.

“When we got here, obviously, public safety was my number one concern. We could not have animals running loose in this county.”

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.

Sam Kopchak, Thompson’s neighbor, said he saw lions and bears running free Tuesday evening. A tiger was chasing horses, he said.

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 being 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 the city 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.

Thompson had his run-ins with the law. He pleaded guilty this year to federal charges of possessing illegal firearms, including five fully automatic firearms, and was released from prison September 30. A civil case seeking forfeiture of firearms is pending, according to the U.S. attorney’s office in Ohio’s Southern District.

Thompson also was convicted of animal cruelty and animals at large in 2005 and was arrested several times for traffic violations.

Lutz said law enforcement officials were well aware of Thompson’s animals and made numerous visits to the property to look into complaints and ensure that Thompson was in compliance with permits

Thompson’s property is about 2 miles outside Zanesville, Zwelling said. Authorities said they received reports of animal sightings by residents. Columbus Zoo director emeritus Jack Hanna drove into Zanesville overnight to assist in the search.

But Hanna warned that the search was dangerous and said human life came first.

“We’re trying our best to make sure no one is hurt doing this,” he said.

He said the animals were probably hiding out from the rain, but his advice to anyone who encountered one was this: Don’t run. Just scream.

The menagerie of Thompson’s animals also included wolves, giraffes and camels. Commuters reported seeing bears and wolves along Interstate 70. Lutz said one cat was hit and left wounded on the road.

The Humane Society of the United States urged Ohio officials Wednesday to issue an emergency rule to crack down on exotic animal ownership.

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, Ninette Sosa, Ed Payne and Maggie Schneider contributed to this report.