Geneva — A private dinner gathering in a dome tent at a campsite in Giswil, central Switzerland, turned dangerous on Saturday evening, leaving more than two dozen individuals hospitalized due to carbon monoxide poisoning, authorities confirmed.
The incident occurred during a large private dinner party at the Giswil campsite, situated in the scenic Obwalden canton. According to the regional police, 35 individuals attended the event, which began as a festive occasion but ended in chaos when attendees began experiencing symptoms of poisoning.
Guests Collapse Amid the Celebration
At approximately 10:30 PM local time (2130 GMT), multiple attendees suddenly lost consciousness while others reported feeling unwell. In response, the group promptly evacuated the tent and sought fresh air, which likely prevented further harm. Emergency services were alerted and swiftly arrived on the scene to provide medical assistance.
Obwalden police stated in a press release, “Late on Saturday evening, a number of people in Giswil suffered from carbon monoxide poisoning and had to be hospitalized.” Victims were transported to nearby hospitals, with several requiring intensive care.
Initial Investigation Points to Dangerous Gas Accumulation
Preliminary investigations revealed a dangerous buildup of carbon monoxide in the dome tent as the cause of the poisoning. While the exact source of the gas remains under investigation, such accumulations are often linked to the use of improper heating or cooking equipment in poorly ventilated spaces.
The police emphasized that carbon monoxide is a colorless, odorless gas that can cause severe health issues, including loss of consciousness and, in extreme cases, death. Symptoms of poisoning include dizziness, headaches, nausea, and confusion—all of which were reported by the affected attendees.
Campground and Police Authorities Respond
Local authorities have cordoned off the campsite area for further investigation. In a statement, Obwalden police urged caution when using gas-powered devices in enclosed or semi-enclosed spaces. “We strongly recommend ensuring proper ventilation and following safety guidelines when operating heating or cooking devices to avoid similar tragedies,” they said.
The Giswil campsite management expressed its concern and support for the victims and their families. “We are fully cooperating with the ongoing investigation and remain committed to ensuring the safety of all guests,” a spokesperson for the campsite stated.
A Reminder of Carbon Monoxide Dangers
This incident serves as a stark reminder of the risks associated with carbon monoxide, particularly in temporary structures like tents or camping domes, where ventilation is often insufficient. Experts advise using carbon monoxide detectors and exercising vigilance when using gas-powered appliances in such settings.
The victims’ conditions were not immediately available as of Sunday afternoon, but medical professionals continue to monitor their recovery. Authorities have not disclosed whether any fatalities occurred.
Ongoing Investigation
Obwalden police have launched a full inquiry into the incident, including an analysis of the heating and cooking devices used during the event. Further updates are expected as investigations proceed.
The tragedy has left the local community shaken and raised awareness about the critical importance of safety precautions when enjoying outdoor gatherings.

