One of the physics world's most complex machines has become temporarily immobilised by a small woodland creature.
The world's largest atom smasher, the Large Hadron Collider (LHC) near Geneva, has suspended operations after a weasel invaded a transformer that helps power the machine and set off an electrical outage on Thursday night.
The "severe electrical perturbation" affected all accelerators and damaged transformer connections, the European Organization for Nuclear Research (CERN) said in its report of the last 24 hours.
In 2012, scientists discovered the Higgs Boson - nicknamed the "God particle" - without which the universe would be cold, dark and lifeless.
It is hoped the LHC will help scientists explore new realms of physics and could yield evidence of hidden extra dimensions and dark matter.
CERN said it will take days for the machine - about the size of the London Underground's Circle line - to recover fully, adding it was "not the best week for LHC!".
Authorities say the incident was one of several small glitches that will delay plans to restart the $4.4 billion collider by a few days.
Little remains of the weasel which, as you might expect, died during its unfortunate encounter.
A twitter account has been set up in its memory.