Three concerned US senators were briefed by the Pentagon Wednesday about the US Navy’s numerous encounters with unidentified flying objects (UFOs), judging them to be “a safety concern.”

“Navy officials did indeed meet with interested congressional members and staffers on Wednesday to provide a classified brief on efforts to understand and identify these threats to the safety and security of our aviators," US Navy spokesperson Lt. Cmdr. Daniel Day said in a statement, noting that "follow-up discussions with other interested staffers" would happen the following day.

"Navy officials will continue to keep interested congressional members and staff informed. Given the classified nature of these discussions, we will not comment on the specific information provided in these Hill briefings.”

Politico reported that one of the attending lawmakers was Senate Intelligence Committee vice-chair Mark Warner (D-VA), according to his office.

“If pilots at Oceana or elsewhere are reporting flight hazards that interfere with training or put them at risk, then Senator Warner wants answers,” Warner’s spokesperson, Rachel Cohen, said in a Wednesday statement. “It doesn’t matter if it’s weather balloons, little green men, or something else entirely — we can’t ask our pilots to put their lives at risk unnecessarily.”

In April, the Navy announced it was drawing up new guidelines to encourage its aviators to report UFO encounters in an effort to destigmatize the subject, Sputnik reported. Now, “there are people coming out of the woodwork,” according to one former government official who participated in the meetings.

A current intelligence official added: “More requests for briefings are coming in.”

Indeed, the New York Times reported late last month on the “almost daily” appearances of UFOs on F/A-18 Super Hornet radars following a 2014 upgrade - many of which were confirmed by visual contact. The UFOs were reportedly capable of hypersonic speeds and accelerations that would be deadly for human pilots.

US President Donald Trump was even asked about the mysterious sightings, telling ABC he’d been briefed on them but did “not particularly” believe them.

At one point, the Pentagon took UFOs very seriously. Between 1952 and 1969, the Air Force’s “Project Blue Book” embarked on a series of studies to determine once and for all what all these UFOs being seen and reported were. While visitors from another world were one possible explanation, it was considered far more likely that unidentified phenomena might be either natural effects or some top secret weapons project being tested by the Soviet Union.

The program closed in 1969, when the Air Force decided UFOs were "no longer of any interest." However, as Sputnik reported, the investigation didn't end: the Defense Intelligence Agency (DIA) revived the program in 2009 as the Advanced Aviation Threat Identification Program (AATIP). While the Pentagon maintains the project ended three years later, its former chief, Luis Elizondo, claims he continued to oversee its operation until his resignation in October 2017.