Commerce City, CO – Three people at a home in Commerce City were sent to the hospital to be treated for carbon monoxide poisoning Tuesday, the South Adams Fire Department said.

A call to 911 reported at sick person at the home in the 8600 block of Laurel Drive near East 88th Avenue and Interstate 76, the fire department said.

When paramedics arrived, the carbon monoxide detector in the ambulance started going off.It’s not clear whether there was a working carbon monoxide detector in the home.

There were four people in the home at the time. One person refused treatment, but three others were taken to the hospital.

Xcel Energy was at the scene to investigate the cause.