THE rancher called Chuck Zukowski in a panic.

“I think it’s happening again,” the farmer named Miller said nervously, in 2011.

“I’ll be right there,” Zukowski reassured him.

The 58-year-old alien investigator threw on his tactical vest, jumped into his black Ford truck and sped over to Miller’s farm two hours away in Colorado.

The spooked cattleman greeted Zukowski with a solemn stare and pointed toward the carcass of a cow plopped in the dirt.

The mutilated red angus was missing its ears, tongue and genitalia, similar to the previous two incidents at Miller’s ranch, Zukowski told the New York Post.

Each body part was dissected in a clinical way, leaving cauterised surgical wounds, but the earth surrounding it was left completely undisturbed.

Zukowski had no doubt that this was the work of aliens, and they were once again operating on the 37th parallel.

“I started to realise the cattle mutilations, UFO sightings and major events like Area 51 all lined up,” Zukowski said, referring to the 37th degree of latitude, which forms the borders between Utah and Arizona, Colorado and New Mexico, and Kansas and Oklahoma.

He’s investigated more than 1000 paranormal incidents over 30 years, and 200 of them landed on the 37th parallel.

“It’s America’s paranormal highway,” the self-described “UFO nut” proclaimed.

Zukowski believes the aliens have a predilection for places with a proximity to underground water and a high level of hydrogen, which they use for energy.

He became fascinated with extraterrestrials as a kid, but began to get serious about his “research” in the late 1980s.

On weekends, he’d pile his three kids and his wife, Tammy, 56, into a beat-up RV to go UFO hunting. Like the Ghostbusters, Zukowski is always fully strapped for action.

“I never go anywhere without a tactical vest, a gun, a full-spectrum camera, a handheld metal detector, binoculars, a rangefinder and glass tubes for samples,” he boasted.

When he moved his family out to Colorado Springs in 1998, he latched on to the phenomenon of mutilated animals.

“They all look as if someone has cut them up with a surgical knife,” he said.

Zukowski, who works as a microchip designer, sharpened his investigative skills while working for the local Sheriff’s Department, earning him the nickname “Mulder of El Paso” after the X-Files character Fox Mulder.

But eight years later, he was booted from the squad for his paranormal leanings.

“They thought it hurt the integrity of the department and were embarrassed,” he said.

Not so for writer Ben Mezrich, whose book The Accidental Billionaires was adapted into the movie The Social Network.

When Mezrich caught wind of Zukowski’s quest “to find the truth,” he flew to Colorado to meet the subject of his forthcoming book The 37th Parallel: The Secret Truth Behind America’s UFO Highway, which comes out on Friday.

The movie rights have already been snapped up by New Line Cinema.

“He swept me up from the airport, gave me a bulletproof vest and a gun and said, ‘Let’s go investigate UFOs!’” Mezrich said of his first encounter with Zukowski.

“I was blown away by his obsession.”

Lots of people ridicule UFO researchers, but Mezrich was infatuated with Zukowski’s commitment to finding aliens.

For the following six months, Mezrich dived headfirst into Zukowski’s theory.

“Over the course of my research, I’ve determined it’s incredibly likely that we have been visited by aliens at least once,” he said.

SCEPTICAL? READ THE EVIDENCE FOR YOURSELF

1. Area 51 — Lincoln County, Nevada

This US Air Force facility about 140km north of Las Vegas has been shrouded in mystery since the late 1940s. UFO investigators believe alien remains and spacecraft are kept at Area 51 — including a wrecked spacecraft and alien remains supposedly found in 1947 in Roswell, New Mexico.

Zukowski got his first look at Area 51 in 1995, when he hired a guide to take him to Tikaboo Peak. From there, he could view Area 51 from 30km away. During his visit, he snapped a photo of what he believes was a flying saucer.

2. Dulce underground base — Dulce, New Mexico

Many believe an underground military and alien base exists underneath this small New Mexican town. Since 1979, a number of people have come forward claiming to have worked at the facility.

One released a bundle of documents — known as “The Dulce Papers” — purporting to contain details about the base.

Numerous area residents have reported seeing alien spacecraft. Zukowski has visited Dulce several times over the past decade, and has spoken with members of the Jicarilla Apache Nation about their experiences with aliens.

“It doesn’t matter who you speak with — everyone agrees there is an underground base nearby,” Zukowski said.

3. Taos hum — Taos, New Mexico

A mysterious humming noise is said to have plagued the town of Taos since the early 1990s.

Zukowski is among those who believe the hum comes from construction of an underground human and alien base.

Residents find the noise annoying. Some claim it causes dizziness, insomnia, sleep disturbance and headaches.

Researchers determined that about two per cent of the population in Taos were “hearers.” However, there has been no evidence to prove that the humming really exists. Zukowski visited the town in 1996, but he and his family were unable to hear the hum.

“Even though we didn’t hear it, I was able to speak with a few residents who did,” he said.

4. Miller mutilation — Trinidad, Colorado

In August 2011, Zukowski was called to the Miller ranch to investigate a grisly mutilation of a five-year-old cow.

The cow was missing its udder and teats, tongue, and left ear and had oval-shaped holes between its forelegs and rear. The dirt surrounding the animal seemed undisturbed and there were no footprints to be found, according to Zukowski.

“What was particularly odd about this one was when I came back a few weeks later, I noticed the bottom ribs were cracked. The only explanation is that it was dropped on the ground from a high distance,” he said. The Las Animas County Sheriff deputy investigated the death, but was unable to determine a cause.

5. Sanchez mutilation — San Luis, Colorado

Zukowski investigated a spine-tingling mutilation on Manuel Sanchez’s ranch in November 2009.

A five-month-old calf had its guts completely hollowed out, its legs broken and bent backwards, and its body twisted like a corkscrew.

It was the fourth calf on Sanchez’s ranch viciously mutilated over the previous three weeks. “The rancher was so distraught, that he took the rest of his calves to auction,” Zukowski said. He figured selling them was better than losing more to mutilation.

6. UFO sighting — Wichita, Kansas

An anonymous Wichita resident claimed to see a UFO “radiating its own light” in May 2011.

“I saw a light in the sky. The only way I can describe it is the light was different from a star,” the man told the National UFO Reporting Centre.

He spotted the peculiar light around two in the morning while he was outside smoking a cigarette a few miles from McConnell Air Force Base.

“I studied it for about 10 minutes and noticed it was oscillating slightly and making very small, rapid movements,” he said.

7. Piedmont UFO phenomenon — Piedmont, Missouri

Since February 1973, hundreds of Piedmont residents have reported seeing flying objects and mysterious lights in the sky.

A local high school basketball team supposedly witnessed a bright shaft of light beaming down from the atmosphere and noticed an object hovering in the distance.

As the sightings continued, residents started to gather at a nearby landfill to watch the lights together, according to Zukowski.

Zukowski has visited the area numerous times and has talked to locals about what they saw. “The most recent time I was there, I talked to two women who actually saw the craft,” he said.

8. UFO crash and retrieval — Cape Girardeau, Missouri

A Baptist minister was called to an apparent plane crash in 1941 to perform last rites for the deceased. But at the crash scene, the minister supposedly didn’t see humans at all.

Instead, he saw a disc-shaped object surrounded by tiny grey people. After the minister prayed for them, he was escorted away by the FBI.

Zukowski believes he has discovered the crash site, which is now a gravel pit. “The gravel pit had destroyed any topography evidence of a crash,” he said.

9. Mantell UFO incident — Owensboro, Kentucky

Captain Thomas Mantell was pilot for the Kentucky National Guard in 1948 when he received orders to fly after an unusual aerial object.

The 25-year-old pilot took off after the craft in a P-51 Mustang fighter plane. Supposedly he crashed and died as he pursued the UFO.

Believers say Mantell reported by radio that he could see tiny creatures in the mysterious aircraft. The Air Force announced that his death was a result of oxygen deprivation and that he was chasing after the planet Venus.

Zukowski believes the announcement was a government attempt to “keep real information from the public.”

10. UFO sighting — Roanoke, Virginia

In December 2010, a Roanoke resident reported seeing a disc-shaped orb zipping through the clouds.

The witness was seeking a shortcut down a country road that turned out to be a dead end. As the car retraced the route, its passenger saw the mysterious aircraft “moving westward at a very fast pace.”

The object also gave off a “light blue aura and moved up and down without sound,” the report to the National UFO Reporting Centre reads.

WHAT YOU NEED TO TRACK DOWN AN ALIEN

Chuck Zukowski put together his UFO investigator vest in 2014:

— Law-enforcement tactical vest that weighs about 11kg with all his gear

— Six-centimetre steel pocket knife

— Leatherman multipurpose knife

— Flashlight that can illuminate blood on the ground

— Walkie-talkie, for when he travels in a team

— Glock pistol

— Garmin GPS, for when he’s travelling on foot

— Law-enforcement-grade handheld metal detector

— Trifield EMF meter, used to detect electromagnetic fields

— A full-spectrum digital camera modified to work in all modes of light

— Glass vials, to store samples

— Geiger counter

— Binoculars

This article originally appeared in the New York Post, and was reproduced with permission.