Philadelphia, PA – Officials say five people were sickened by carbon monoxide fumes in an apartment building in the city’s Logan section early Thursday morning.

Fire and hazmat crews were called around midnight to the 400 block of East Wister Street.

Authorities say five people were sickened from carbon monoxide fumes from an apartment building located on the Woodford Tennis Club property.

Three were taken to the hospital in stable condition.

PGW tells Action News a heater malfunctioned, allowing CO fumes to leak into at least one of the apartments.