CHUALAR, Calif. —Cue “The X-Files” song. Mysterious, giant crop circles have appeared on a Chualar farm and startled observers into wondering if aliens landed in the Salinas Valley.

VIDEO: Locals wonder who — or what — created Chualar farm crop circles

Two friends were driving on Chualar Canyon Road south of Salinas just before dawn Sunday when they witnessed strange bursts of green light flashing on the horizon. The duo turned on a video camera, pulled over, hopped a barbed-wire fence, and walked toward the lights.

“Dude, are you seeing this?” one friend said. “Dude, this is a crop circle.”

PHOTOS: Intricate crop circles in Chualar

The friends investigated the field until they panicked and sprinted away. The duo wanted to remain anonymous, and they uploaded a video of their experience on YouTube under the name Cannot Say.

“Needless to say, pretty wild. But we slipped away and it’s too good not to share,” Cannot Say wrote.

No one realized how intricate the crop circles were until professional photographer Julie Belanger took a helicopter ride Monday morning. Belanger had not heard about the circles and she flew in a helicopter over the farm by coincidence.

Belanger said her first immediate thought was, “What is it?”

“It was beautiful. Quite beautiful,” Belanger told KSBW. “I believe it’s possible that aliens exist, but I don’t know if they would bother making a crop circle to give us a message.”

Curious onlookers grew in number Monday afternoon as word of the crop circles spread. People stood on top of vehicles and fences to get a better view, and security guards kept gawkers from entering the field.

“I’m always willing to believe. It looks like aliens to me,” Manuel Madrid of Gonzales said.

While alien believers marveled, skeptics sounded off to debunk any extraterrestrial Chualar theories.

KSBW.com reader Russell Martin commented, “The Ancient Chualarians have always been known to be a bunch of merry pranksters.”

Michael Myers commented, “Yes they mastered Intergalactic travel and can’t make a perfect circle.”

Paige Penrose chimed in, “That looks really neat, regardless of who did it! Great design.”

As of Monday night, no one had stepped forward to claim responsibility for the crop circles.