London, Oct 8 : UFOs "have been here since 1947", according to a British expert, who added that an alien crashed in the United States in the same year.
Philip Mantle, the editor of UFO Data Magazine, is unveiling his findings at an international conference this month.
He investigated the site in Roswell, New Mexico where many people believe there was an alien crash landing. He analysed rock, earth and vegetation.
The area is surrounded by charred trees and bushes and a mysterious blue substance that dribbles down rocks.
US physician Dr Ronald Rau said in the 1940s high levels of radiation pointed to a ship landing there in the 1940s.
The area in the Nogal Canyon is close to the well-known Socorro desert site where experts say another object appeared to have landed in 1964.
"A good friend of mine Ed Gerham first found the site and I flew over as soon as I could," Telegraph quoted Mantle, as saying.
"It was a real find and as soon as I arrived there I knew what a special and peculiar place it was. There is nothing around it for around 70 miles, it is literally in the middle of nowhere.
"Us Brits really have beaten the Americans at their own game and it is really great that we have done that. It really is revolutionary for the UFO world."
Mantle is set to reveal his full findings at the UFO Data Annual Conference in Leeds.