A manhole explosion sent fire and black smoke in the air this morning around 9:30 on 37th Street between Seven and Eighth Ave in Manhattan, NYC. The explosion caused several buildings nearby to loose power for some time. One building was reported to have no power for at least 8 hours. It took several hours for the firefighters to stop the fire that was coming out of the manhole. Manhole explosions often happen when the rain brings down the salt from the winter into frayed wire or when rats gnawed at the wire. An investigation is ongoing to determine the cause of this specific explosion. read more on NBC New York.