Reports that the Large Hadron Collider had detected the first possible signs of the elusive Higgs boson particle were "wrong", experts have said.
Last month, an internal memo outlining a possible signal from the Higgs picked up at the LHC was leaked on to the web.
But cross-checks of the data collected by the Atlas experiment have since found no signal.
The details were revealed during a talk by senior officials at the Royal Society in London.
The Higgs boson is of huge importance to the widely accepted theory of physics, known as the Standard Model.
It is the sub-atomic particle which explains why all other particles have mass, but no-one, so far, has detected it.
The result which had been under discussion originated with four members of the Atlas collaboration.
Atlas is one of two "multi-purpose" experiments at the LHC designed to search for the Higgs, and some 3,000 physicists are working on the project.
Professor Fabiola Gianotti, who is spokesperson and overall coordinator for the Atlas detector, said a closer look at the data from the experiment had found no signal that could indicate the Higgs.
"This is why we don't want to release any results until we are sure that we are satisfied that they are true," she told BBC News.
The director-general of Cern, Rolf-Dieter Heuer, said that Cern's management was "not very amused" by the leak.
He commented: "This should be a lesson to journalists not to report results they might see from blogs. If we do discover something and we are sure of it we will announce it officially. Any other news is speculative."
The result at Atlas had targeted the Higgs in a mass region of 115 gigaelectronvolts (GeV), where candidates had previously been observed by the LHC's predecessor - the Large Electron Positron (LEP) collider.
They observed a so-called "resonance", an effect which can be associated with the presence of sub-atomic particles.
But the number of events seen by the researchers was about 30 times greater than would be expected.
The note was originally posted on the Not Even Wrong physics blog by an anonymous user.