Allentown, PA – An investigation is underway tonight after an apparent carbon monoxide poisoning sends four people to the hospital.

Reading firefighters were called to the 300 block of North 10th Street where two contractors were working in the basement of a row house. Firefighters say they found one contractor unconscious and the other one partially conscious.

They believe the pair may have been poisoned when a generator stopped working. Two elderly women in the home next door were also taken to the hospital.