A Navy official has confirmed that recently released videos of unidentified flying objects are real, but that the footage was not authorized to be released to the public in the first place.

Joseph Gradisher, the spokesman for the Deputy Chief of Naval Operations for Information Warfare, confirmed to TIME that three widely-shared videos captured “Unidentified Aerial Phenomena.”

Gradisher initially confirmed this in a statement to “The Black Vault” a website dedicated to declassified government documents.

“The Navy designates the objects contained in these videos as unidentified aerial phenomena,” Gradisher told the site.

He tells TIME that he was “surprised” by the press coverage surrounding his statement to the site, particularly around his classification of the incursions as”unidentifiable,” but says that he hopes that leads to UAP’s being “de-stigmatized.”

“The reason why I’m talking about it is to drive home the seriousness of this issue,” Gradisher says. “The more I talk, the more our aviators and all services are more willing to come forward.”

Gradisher would not speculate as to what the unidentified objects seen in the videos were, but did say they are usually proved to be mundane objects like drones—not alien spacecraft.

“The frequency of incursions have increased since the advents of drones and quadcopters,” he says.

In December 2017 and March 2018, three videos of UFOs were published by the New York Times and “To the Stars Academy of Arts and Science“, a self-described “public benefit corporation” co-founded by Tom Delonge, best known as the vocalist and guitarist for the rock band, Blink-182.

The first of the videos, known as the “GIMBAL footage” shows a 2004 encounter near San Diego between a Navy fighter jet and an unidentified aerial phenomenon.

The video was featured in a December 2017 story by New York Times about the U.S. Defense Department’s “Advanced Aerospace Threat Identification Program,” which studied videos of encounters between unidentified aerial phenomena and U.S. military aircraft.

According to Gradisher, investigations into unidentified objects are driven by the danger they pose to pilots.

“Incursions by [unidentified aerial phenomena] represent a safety hazard to aviators and security issues for operations,” he tells TIME. “The Navy is investigating the incursions seen in the three videos,” adding that sightings “occur frequently.”

Gradisher explained to the Black Vault why the Navy prefers the term unidentified aerial phenomena over “UFO.”

“The ‘Unidentified Aerial Phenomena’ terminology is used because it provides the basic descriptor for the sightings/observations of unauthorized/unidentified aircraft/objects that have been observed entering/operating in the airspace of various military-controlled training ranges,” he told the site.

Gradisher also goes on to say that the videos published in May by the Times were not approved for public release by the U.S. government, despite claims from To the Stars Academy of Arts and Science.

“The Navy has not released the videos to the general public,” he told The Black Vault.

Gradisher tells TIME the Navy is aware that the 2004 video was shared and posted online by a crew member, but could not account for how the other two videos were released.

He says there is “very much an ongoing investigation,” into the objects seen in those videos.

In response to reports on Gradisher’s statements, To the Stars Academy of Arts and Science uploaded a Facebook post that said, “The U.S Navy has officially acknowledged that UFOS are real and violate American airspace.”

Write to Gina Martinez at gina.martinez@time.com.