An underground electrical fire in downtown West Chester spread to two buildings’ electrical panels and caused a Carbon Monoxide buildup that sent five fire fighters to Chester County hospital. Smoke was first reported around 3:30 p.m. near the Chester County Justice Center on West Market Street. Firefighters then received a call for two fires in basements on the 200 block of West Gay Street. When fire fighters entered the buildings, a buildup of Carbon Monoxide from the underground fire caused West Chester Assistant Fire Chief Mark Scanlon to collapse while exiting the building. According to Fire Chief Mike McDonald, Scanlon was treated at the scene where he briefly lost consciousness and will be kept overnight for observation. Four other firefighters are expected to be released tonight from the hospital. The fire was totally extinguished by 7 p.m. Six families in the 200 block of West Gay Street were evacuated and are expected to be allowed back in their homes once PECO restores power. PECO officials were unavailable for comment.