Authorities said elevated levels of carbon monoxide in a Union home sent three people to the hospital Sunday night.
According to authorities, EMS responded to the 1500 block of Julian Terrace before 9 p.m. for a report of an unresponsive person.
While en route dispatch advised the EMS unit that now a second patient was unresponsive at the same address.
Firefighters were immediately dispatched, and upon their arrival, crews entered the home and found elevated CO readings on their meters
Officials said the initial readings were 100 at the front door and over 900 in the basement.
Firefighters immediately shut down the furnace before they ventilated the house.
Three victims were treated and ultimately transported with possible CO poisoning officials said.
According to family members, the family dog apparently succumbed from CO poisoning.