The US government has said it has no explanation for dozens of unidentified flying objects seen by military pilots.
A Pentagon report released on Friday says of 144 reports made about the phenomena since 2004, all but one remain unexplained.
It does not rule out the possibility that the objects are extra-terrestrial.
Congress demanded the report after the US military reported numerous instance of objects seen moving erratically in the sky.
The Pentagon then established the Unidentified Aerial Phenomena Task Force last August to look into the reports.
The group’s job was to “detect, analyse and catalogue” these events, as well as to “gain insight” into the “nature and origins” of UFOs, the Pentagon said.
Did the report reveal anything new?
The interim report released on Friday said most of the 144 reported cases of the “unidentified aerial phenomena” (UAP), came in the last two years, after the US Navy put in place a standardised reporting mechanism.
In 143 of the reported cases, they “lack sufficient information in our dataset to attribute incidents to specific explanations”.
Crucially, it said there were “no clear indications that there is any non-terrestrial explanation” for the aircraft, but also did not rule it out.
UAP “probably lack a single explanation”, the report said. Some could be technologies from another nation like China or Russia, others could be natural atmospheric phenomena like ice crystals that could register on radar systems, while the report also suggested some could be “attributable to developments and classified programs by US entities”.
The one case they could identify “with high confidence” was identified as “a large, deflating balloon”, the report said.
It added that the UAP posed “a clear safety of flight issue and may pose a challenge to US national security”.
The taskforce is now “looking for novel ways to increase collection” of reports and gather more information, adding that “additional funding” could “further study of the topics laid out in this report”.
What evidence is there?
The US Department of Defense released videos of the UAPs in April 2020. It said they had been filmed by the US Navy.
In a CBS News 60 Minutes episode last month, two former Navy pilots discussed seeing an object in the Pacific Ocean that appeared to mirror their movements.
One pilot described it as a “little white Tic-Tac-looking object”, referring to the white oblong mints.
“And that’s exactly what it looked like, except it was travelling very fast and very erratically and we couldn’t anticipate which way it was going to turn or how it was manoeuvring the way that it was, or the propulsion system,” witness and former Navy pilot Alex Dietrich told BBC News.
“It didn’t have any apparent smoke trail or propulsion. It didn’t have any apparent flight control surfaces to manoeuvre in the way that it was manoeuvring.”