MONROE, Utah (AP) — Twenty-two people were hospitalized for carbon monoxide poisoning over the weekend at a Church of Jesus Christ of Latter-day Saints church in central Utah, authorities said Monday.

Emergency personnel initially responded to two medical calls on Sunday at the church in the small city of Monroe, the Sevier County Sheriff’s Office said. The calls involved a four-year-old girl with breathing problems and a man who was feeling sick.

After a third call involving a family with headaches, the Monroe City Fire Department checked the building and found elevated levels of carbon monoxide, prompting the church to be evacuated.

More people reported being ill later in the evening and police said in all 22 individuals were taken to out-of-area hospitals with hyperbaric chambers where the victims could be treated.

The source of the carbon monoxide poisoning had not been determined.