MOSCOW, June 11. /TASS/. Scientists of the Russian Academy of Sciences are investigating the sightings of so-called UFOs in the history of humankind, Roscosmos Director General Dmitry Rogozin said on Saturday.

"If we talk about specific facts of the so-called UFO [sightings], which might have taken place on Earth throughout the history of mankind, which NASA speaks about, I would like to say that these studies have been conducted and are being conducted by our [Russian] Academy of Sciences among others. The facts are collected and checked," Rogozin said in a televised interview with Rossiya-24 news channel.

According to the Russian space agency chief, 99.9% of the sightings are some atmospheric or other physical phenomena that are not related to the real hypothesis of the UFOs.

"However, we admit that such phenomena could have taken place," he stressed.

Rogozin added that he is personally familiar with the testimonies of pilots who saw unusual phenomena during their test flights back in the 1970s and then took a pencil and paper to sketch out what they had witnessed.

"Usually, what we are talking about appeared during a first test flight. I have talked to NASA, and there are proponents there too that we may be the object of external observation. I would like to believe it," the Roscosmos chief added.

NASA announced earlier that it was setting up a team of researchers to study sightings of unidentified flying objects (UFO) from a scientific perspective.