The New York Post reported Wednesday, citing local media outlets, that the party had to be called off after a large amount of faeces was found in the water on a beach on the Spanish island of Ibiza.

The San Josep City Council has closed Playa Pinetto beach after swimmers were put at risk of E. coli infection after it found fecal matter in the water that exceeded safety guidelines, The New York Post reported. “This decision was taken as a temporary solution while the Department of the Environment is investigating the source of the contamination,” the city council said in a statement, according to the New York Post. (Related: Contaminated water increases death toll in Puerto Rico)

E. coli is a bacterium that normally lives in the human gut and can only cause short-term diarrhea when ingested. according to to the Mayo Clinic. But eating undercooked food and contaminated water “can cause severe stomach cramps, bloody diarrhea and vomiting,” and in extreme cases can be fatal, the clinic said.

Ibiza tourist beach closed after nasty discovery in waters https://t.co/o3PGj9LfCf pic.twitter.com/wFdQ0R4Usu

— New York Post (@nypost) July 19, 2023

According to the New York Post, the city council has assured that Playa Pinet’s water will be tested weekly to ensure a safe environment for swimmers.

“We will have data from a second sample in the next 48 hours, but for now this beach is closed to swimming,” the city council said.

Authorities have put up red flags all over the beach to keep tourists from swimming, according to the New York Post.