Muskingum County Sheriff Matt Lutz (loots) also says his department has received numerous complaints since 2004 about animals at the property in eastern Ohio.
The farm owner apparently opened cages that housed dozens of dangerous animals and then committed suicide.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
Schools closed and motorists were warned to stay in their vehicles as officers with assault rifles hunted Wednesday for bears, big cats and other beasts that escaped from a wild-animal preserve after the owner apparently opened cages that housed dozens of dangerous animals and then committed suicide.
Officers were under orders to shoot to kill because officials said it wasn't safe to tranquilize the animals in the dark.
Muskingum County Animal Farm owner Terry Thompson killed himself after freeing the animals, Muskingum County Sheriff Matt Lutz said Wednesday, following a night during which officials hunted down and shot to death nearly 30 of the 48 animals.
As officials warned that more animals still were on the loose, three school districts in the region and some private and special schools canceled classes as the remaining bears, big cats and other beasts from the Muskingum County Animal Farm were hunted down.
Flashing signs along area highways told motorists, "Caution exotic animals" and "Stay in vehicle."
The animals' cages had been opened and the farm's fences had been left unsecured, police said.
The preserve in Zanesville, about 55 miles east of Columbus, had lions, tigers, cheetahs, wolves, giraffes, camels and bears. Police said bears and wolves were among the escaped animals that were killed and there were multiple sightings of exotic animals along a nearby highway.
Lutz called the animals "mature, very big, aggressive" but said a caretaker told authorities the animals had been fed on Monday.
Tuesday night, more than 50 law enforcement officials - including sheriff's deputies, highway patrol officers, police officers and officers from the state Division of Wildlife - patrolled the 40-acre farm and the surrounding areas in cars and trucks, often in rainy downpours. Lutz said they were concerned about big cats and bears hiding in the dark and in trees.
Neighbor Danielle White, whose father's property abuts the animal preserve, said she didn't see loose animals this time but did in 2006, when a lion escaped.
"It's always been a fear of mine knowing (the preserve's owner) had all those animals," she said. "I have kids."
Lutz said his office started getting phone calls at about 5:30 p.m. Tuesday that wild animals were loose just west of Zanesville on a road that runs under Interstate 70.
He said four deputies with assault rifles in a pickup truck went to the animal farm, where they found the owner Thompson dead and all the animal cage doors open.
He wouldn't say how Thompson died but said several aggressive animals were near his body when deputies arrived and had to be shot.
Thompson, who lived on the property, had orangutans and chimps in his home, but those were still in their cages, Lutz said.
The deputies, who saw many other animals standing outside their cages and others that had escaped past the fencing surrounding the property, began shooting them on sight.
Staffers from the Columbus Zoo went to the scene, hoping to tranquilize and capture the animals after daybreak Wednesday. The zoo's director emeritus, TV host Jack Hanna, said that was something that could not be done in the dark.
"You cannot tranquilize an animal like this, a bear or a leopard or a tiger (at nighttime)," Hanna told ABC's "Good Morning America on Wednesday. "If you do that, the animal gets very excited, it goes and hides, and then we have his (Lutz's) officer in danger of losing their life, and other people."
He further defended Lutz' action at a news conference in Zanesville, saying there was no other choice with normally captive animals loose at night in the rain.