An alleged alternative medicine conference in Germany ended abruptly after dozens of participants took hallucinogens and began “staggering around, rolling in a meadow, talking gibberish and suffering severe cramps.”

According to The Independent, the 29 drugged people were discovered Friday at the hotel where they held their conference in the town of Handeloh. The UK paper also reports that 150 medical staff, ambulances and police were required to deal with the situation and take the patients to a nearby hospital.

It remains unclear whether the hospitalized individuals took the hallucinogenic drug–2C-E, also known as Aquarust–willingly, or whether they ingested it unwittingly. Torsten Passie, MD, PhD, speaking to local news outlet NDR on behalf of Germany’s commission for narcotics, said he thought the sheer number of overdoses “does not support the view that the people concerned took the hallucinogen knowingly…one has to assume that [these] people were not told about the substance, its effects, and risks before taking it.”

NDR speculates that the mass overdose could have been either the outcome of an ill-advised experiment or a "macabre joke.”

The Association of German Healing Practitioners says it was not aware of the “obscure” event, and that its organizers were unknown to them:

“Unfortunately, the conference in Handeloh has severely damaged the image of the alternative medicine profession…and we have clarified that such acts are not in the spirit of natural therapy, and contradict our values both morally and legally…The Association of German Healing Practitioners (Heilpraktikers) detests such misdemeanors.”

The patients, whose ages range from 24 to 56, are allegedly not yet coherent enough to be questioned by authorities. Their symptoms include suffering from delusions, breathing problems, racing hearts and cramps, with some in a serious condition, Deutsche Welle reports.

Blood and urine tests revealed Aquarust as the drug in their systems, which has been illegal in Germany since last year.