A weasel-like animal shut down the world’s largest and most powerful particle accelerator near Geneva, Switzerland, early Friday after weaseling into a transformer.

CERN’s Large Hadron Collider experienced a “severe electrical perturbation” that “damaged” transformer connections due to a “short circuit caused by fouine,” according to a briefing that the organization published. The French dictionary Larousse translates “fouine” as both a weasel and a beech marten.

A CERN spokesperson Arnaud Marsollier told NPR that such accidents can happen, given the facility is in the countryside.

As the organization’s own briefing joked, “Not the best week for LHC!”

Get The Brief. Sign up to receive the top stories you need to know right now. Please enter a valid email address. Sign Up Now Check the box if you do not wish to receive promotional offers via email from TIME. You can unsubscribe at any time. By signing up you are agreeing to our Terms of Use and Privacy Policy . This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Thank you! For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Write to Olivia B. Waxman at olivia.waxman@time.com.