Residents of the small Mississippi River town of Louisiana, Missouri were shocked to discover a monster in their midst during the summer of 1972. Throughout July of that year, locals reported encounters with a tall, hairy, bipedal beast, and the sightings caused enough concern that local authorities eventually took up arms and gathered a posse to hunt the creature. But before that, it all started with the terrifying experience of three children innocently enjoying a summer day in rural Missouri.

On the afternoon of Tuesday, July 11th, 1972, Terry and Wally Harrison—8 and 5 years old, respectively—were playing in their backyard with the family dog while their parents were at work; their older sister Doris, 15, had been left at home to watch them.

“Terry and Wally Paul, he’s 5 years old, were out in the back with Chubby, the dog, when I heard Terry start screaming,” Doris told the St. Louis Post-Dispatch. “I looked out the bathroom window and saw it. I started crying and ran into the other room to call Mom on the telephone, and then she and Dad came home.”

Terry and Doris were both said to have gotten a good look at the creature, which was covered in hair from head to toe and speckled with blood from a dead dog it was carrying under one arm.

“It was right by the tree,” Doris said. “Six or seven feet tall, black and hairy. It stood like a man, but it didn’t look like one to me.”

Chubby, the dog, reportedly grew very ill after the sighting; his eyes became bloodshot and he began vomiting violently. He finally recovered after a meal of bread and milk.

Edgar Harrison, 41, the children’s father and a city employee with 21 years of service, heard a strange growling sound outside of their home several days later on Friday, July 14th. Harrison, a deacon in the Pentecostal Church, along with “maybe 50 other persons” were attending a church meeting held at the house.

According to an account written by fortean researcher Loren Coleman:

Around 8:30 [p.m.], the meeting began to break up. As Harrison and a dozen or so members of his congregation lingered, talking, they sighted two “fireballs” soaring from over Marzolf Hill and descending into the trees behind an abandoned school across the street. The objects appeared at five-minute intervals. The first was white and the second green. About 9:15 [p.m.], Harrison heard ringing noises such as might be caused by the throwing of stones onto the metal water reservoir which stands at the top of the hill. The reservoir, which holds a million and a half gallons of water, is in an area where neighborhood children often play. After one especially loud ring, Harrison reported, “I heard something that sounded like a loud growl. It got louder and louder and kept coming closer. At that time my family came running from the house. They began urging me to drive off. “I wanted to wait and see what it was that was making this noise. My family insisted that I drive away, and so I drove down Allen Street across the Town Branch. “I stopped the car and my wife and family told the congregation, ‘Here it comes!’ And those forty people turned and ran down the street.” Police officers Jerry Floyd and John Whitaker went to the Harrison home. They searched the residence but found nothing.

Edgar and Betty’s recollection of events to the St. Louis Post-Dispatch was somewhat vaguer.

“We were having our regular church meeting at my house when we all heard it,” Edgar told the newspaper. “It was kinda like a loud growling noise. We heard it three times. Then it seemed like it was hurt or something. It gave out a large yelp.”

“It sounded like a gorilla,” Betty added. “That’s what it is—a ‘Bigfoot.’ I heard they’ve got one in California and up in Canada.”

Later in the evening Edgar reportedly searched the area with a few others and found an old building from within which came "a moldy, horse smell or a strong garbage smell."

The events so scared Betty that she took the kids and moved in with Edgar’s brother Vivian Houchins, 56, and his wife, saying she’d “never go back up there” to the house where they’d encountered the beast.

While Houchins hadn’t seen the monster himself, he did say that he’d heard and smelled it.

“The odor is worse than any old goat that you ever smelled,” he said. “Its growl is like a bear’s, but a bear doesn’t run on two feet.”

Meanwhile, Edgar Harrison had found that foliage near the site of his children’s encounter had been disturbed, and that whatever was there had left a few faint footprints and black hairs in the area. Edgar decided to hang fish and ham skin on a tree as bait, but it didn't attract any monsters. He also decided to tie his dog up on the hill behind the house, while he sat outside waiting.

“There's something up there,” Edgar said. “We just haven't found it yet."

Marzolf Hill, whereupon Edgar found the foul-smelling domicile and set his dog to watch, quickly became the focal point of the investigation.

The same afternoon as the Harrison children's sighting, Mrs. Clarence Lee, a neighbor who lived only half a block away, reported that she heard the mysterious growling sounds of a creature "carrying on something terrible,” and not long after she reportedly spoke to a local farmer whose dog had gone missing. The speculation at the time was that perhaps the monster had taken it.

On Wednesday, July 19th, following night after night of being called upon to investigate “things people hear,” local police chief Shelby Ward had gathered together about two dozen men and "made three passes up that hill.”

“We didn't find a thing,” he said. “I hope that ends it."

By that time a story was circulating of the monster picking up the rear end of a car and dragging it into the ditch, and witnesses were reporting that the beast was up to 12 feet tall with clawed hands and red, orange, or green eyes.

Ward became concerned that "people are going to go up the hill with guns looking for this thing and somebody's going to get shot."

"We've been up there and we're convinced there's nothing there now," he said. "We've got the hill barricaded off, but you know some kids will get up there at night. More than likely, that's how it all started anyway, some kids making noises."

Still, others were unconvinced that prankish children were to blame.

UFO researcher Hayden C. Hewes, founder of the International Unidentified Flying Object Bureau in Oklahoma City, was impressed by the evidence presented in favor of a monster—including plaster casts made by Edgar Harrison of footprints found on Marzolf Hill. One of the prints was 10 inches long by five inches long, while another was five inches long and curved in the middle with three impressions that resembled toes.

Hewes and his assistant had camped out on the hill the night of Saturday, July 22nd, hoping to at least capture a recording of the growling sounds reported by some witnesses. Despite someone calling the police at 9:30 p.m. that night to report having heard the monster on the opposite side of the hill from where the investigators were camping, they captured no evidence, even after searching the area from where the monstrous sounds came.

“We did not see or smell or hear anything,” Hewes said. “But from the several reports, it’s apparent that something has been sighted.”

Initially, Hewes believed that the monster—which was by then being referred to by the press as Momo, short for Missouri Monster—fit the description of a type of commonly reported UFO occupant. According to Hewes, descriptions of Momo matched what was known as a “giant hairy biped,” further stating that his organization had received almost 300 sighting reports of such creatures from various locations since opening in 1957.

Following Hewes’ visit to Louisiana, it was reported that two farm families saw a circle of flashing lights in the area on Monday, July 24th. Both families reportedly said that the lights hovered in one spot or landed in the distance, staying for approximately five minutes.

Shortly after returning to Oklahoma City, Hewes amended his opinion to include four possibilities: The creature was an “experimental animal” left by an unidentified flying object, it was a prehistoric creature that has survived into the modern era, it was a primate that escaped from a zoo, or it was a hoax. On August 1st Hewes held a press conference to declare that, despite having discovered some hoaxes after interviewing at least 20 people during his investigation into Momo, his belief was that the monster was most likely “an unknown form of hominid, much like the Neanderthal-like man thought to be extinct since prehistoric times.”

“Momo must be taken alive,” Hewes said. “He’s the greatest anthropological find in history.”

No such creature was ever taken, dead or alive.

By early August the sightings and associated fervor surrounding the mysterious monster known as Momo had largely died down, leaving the one residual effect present in every great case involving paranormal phenomena—a persistent, engaging mystery.

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