Ellen Henry is convinced that what she saw in the skies above Santee, California on May 7 was not of this world.

Choosing not to show her face on TV as she still feels spooked by what her camera had captured, Henry showed ABC TV affiliate News 10 a photograph of what she believes to be a UFO.

"What was it doing there," she told News 10. "It was clear and certainly not a bug."

Henry, a member of the Santee Historical Society in San Diego County, was said to be in the area to take pictures of the centennial old Edgemoor Barn to be used in updating the barn's logo.

"I was constantly looking up and around the area, including the sky's background, so I can get it just right," she said.

The barn, above which the UFO was reportedly sighted, sits under several flight paths but Henry said she did not see nor hear any sound of an aircraft.

It was not after she downloaded the photo on her computer that she realised her camera had captured something out of the ordinary.

"I noticed a 'speck' on my LCD screen after I took the shot to check for clarity, and only realized it wasn't a speck," she added.

News 10 tried to get information from the Gillespie Field and MCAS Miramar (Marine Corps Air Station) to confirm the kind of aircraft that flew over Edgemoor Barn that day but neither could provide explanation.

"There is no way this was a commercial aircraft," Henry told News 10.

"I would have heard it, especially as low as it seemed to be. Someone did mention perhaps it was a drone. However, I have not seen any drones that were round or oval, and lacking wings, rudders or propellers -- even the drone that looks like a fly has wings."

According to News 10 reporter Janet Kwak, a UFO hovering above the barn could not be far-fetched given the property's reputation as being haunted as well.

Santee Historical Society, which oversees the barn turned museum, said that the property used to be part of a hospital facility known for its paranormal activities including ghost sightings.

What's more startling for Henry, though, is that her camera allegedly stopped working right after she snapped a shot of the UFO.

"We've checked with the National UFO Reporting Center, there has only been one other UFO sighting in San Diego this month," News 10 said.