this is a fox news alert in new york. updating a breaking news story from pennsylvania. the scene of a powerful explosion, fire and evacuation that happened late wednesday night in a residential section of central allentown, 60 miles north of philadelphia. reports from the scene indicate a house exploded, setting at least three nearby buildings on fire, several people have been injured, including a firefighter. about 750 residents within a two-mile area, or two-block area, i should say, were evacuated baz the fires from underground gas lines and downed powerlines. the evacees include residents from a nearby senior citizens high-rise building. no word on what might have touched off that explosion. one police officer reporting seeing a fireball. and a local news station tells us the blast was heard as far as seven miles away. tune in to the fox news business