Mason City, IA – Authorities say two women were taken to a hospital after they were overcome by possible carbon monoxide in a house near Thornton in northern Iowa.

Cerro Gordo County Sheriff Kevin Pals says a plumber working at the house on Monday notice high levels of carbon monoxide and told the women to leave.

The women started feeling ill and were taken to a Mason City hospital. Their names were not immediately released.

There was no immediate word on the source of the carbon monoxide in the house, which was ventilated.