Madison, WI – Two people suffered carbon monoxide poisoning today in an exhibitors’ camper at the Midwest Horse Fair in Madison.

Rescuers were called to the Alliant Energy Center just before ten this morning.Madison T-V stations said two people in the camper were semi-conscious when they were taken to a hospital. Horse fair spokesman Paul Nemec said others nearby had notified officials, when they saw that a horse at the victims’ trailer had not yet been feed or cared for this morning.

The reports said the camper’s generator was the apparent source of the carbon monoxide — but the incident remains under investigation.