STEPHENVILLE, Texas - In this farming community where nightfall usually brings clear, starry skies, residents were abuzz over reported sightings of what many believed was a UFO.

The reported sightings captured national and international media attention from outlets like the Washington Post, NPR, CNN, the Larry King Show and Canada’s CBC News. The Larry King Show devoted an hour to people who have seen and investigated UFOs and a skeptic who tried to debunk their accounts.

Several dozen people—including a pilot, county constable and business owners—insisted they saw a large silent object with bright lights flying low and fast in the Texas town. Some reported seeing fighter jets chasing it.

“People wonder what in the world it is because this is the Bible Belt, and everyone is afraid it’s the end of times,” said Steve Allen, a freight company owner and pilot who said the object he saw last week was a mile long and half a mile wide. “It was positively, absolutely nothing from these parts.”

While federal officials insist there’s a logical explanation, locals swear that it was larger, quieter, faster and lower to the ground than an airplane. They also said the object’s lights changed configuration, unlike those of a plane. People in several towns who reported seeing it over several weeks have offered similar descriptions of the object.

Machinist Ricky Sorrells said friends made fun of him when he told them he saw a flat, metallic object hovering about 300 feet over a pasture behind his Dublin home. But he decided to come forward after reading similar accounts in the Stephenville Empire-Tribune.

“You hear about big bass or big buck in the area, but this is a different deal,” Mr. Sorrells said. “It feels good to hear that other people saw something, because that means I’m not crazy.”

Mr. Sorrells said he has seen the object several times. He said he watched it through his rifle’s telescopic lens and described it as very large and without seams, nuts or bolts.

Maj. Karl Lewis, a spokesman for the 301st Fighter Wing at the Joint Reserve Base Naval Air Station in Fort Worth, said no F-16s or other aircraft from his base were in the area the night of Jan. 8, when most people reported the sighting.

Maj. Lewis said the object may have been an illusion caused by two commercial airplanes. Lights from the aircraft would seem unusually bright and may appear orange from the setting sun.

“I’m 90 percent sure this was an airliner,” Maj. Lewis said. “With the sun’s angle, it can play tricks on you.”

Officials at the region’s two Air Force bases—Dyess in Abilene and Sheppard in Wichita Falls—also said none of their aircraft were in the area. The Air Force no longer investigates UFOs.

One man has offered a reward for a photograph or videotape of the mysterious object.

About 200 UFO sightings are reported each month, mostly in California, Colorado and Texas, according to the Mutual UFO Network, which came to check on the sightings in the 17,000-resident town of Stephenville.

Fourteen percent of Americans polled last year by The Associated Press and Ipsos say they have seen a UFO.

Erath County Constable Lee Roy Gaitan said that he first saw red glowing lights and then white flashing lights moving fast, but that even with binoculars could not see the object to which the lights were attached.

“I didn’t see a flying saucer and I don’t know what it was, but it wasn’t an airplane, and I’ve never seen anything like it,” Mr. Gaitan said. “I think it must be some kind of military craft—at least I hope it was.”

The Mutual UFO Network held a meeting Jan. 19 where 200 people shared stories about UFO sightings with dozens of people. According to Texas MUFON director Ken Cherry, the accounts from Stephenville are significant. “In an extremely small number of cases will we get a mass sighting like this,” he said Jan. 18 on Larry King Live.

It is the most significant mass sighting since Phoenix in 1997, which was reported by thousands of people, including former Gov. Fife Symington, he said.

“It is really sad, Larry, that, for example, an Air Force general said reports which could affect national security are not part of the Project Blue Book system. That’s a formal statement by an Air Force general. It led to the closing of the old Project Blue Book. You haven’t seen the press grab on to that one, the good cases, the ones that could affect national security. They’re the only ones we care about,” said Stanton Friedman, a UFO researcher. Project Blue Book was a United States Air Force program that studied UFOs. It started in 1952 and ended in 1970.

Larry King Live participant James Fox, maker of the documentary “Out of the Blue,” helped pull together a panel of high-ranking retired military officers, pilots and scientists for a November media event the National Press Club. The group called on the United States government to cooperate with other nations investigating unidentified flying objects and asked that the United States Air Force or the National Aeronautics and Space Administration research the phenomena. Gov. Symington moderated the press conference.

After a skeptic on the CNN program attributed different sightings to flares, slow flying planes in formation, natural lights and optical effects, and untrained observers whose ignorance and bias colored what they saw, Mr. Fox responded.

“If you’re out there somewhere, why can’t we just say, you know what, we don’t know what that was? Why can’t we just say that? Why do we have to find a prosaic explanation to every sighting that exists today? And why are all these qualified radar operators and pilots and high ranking military and government officials from all around the world, why does there have to be a conventional or prosaic explanation to each and every case? Why can’t we just shrug our shoulders and say we don’t know?” he asked.

(Final Call staff contributed to this report.)