Explosion Evacuates St. Louis Office Building

Officials say a blaze that led to the evacuation of one of the largest office buildings in downtown St. Louis originated in an underground vault that houses an electrical transformer.

The cause of the blaze isn't yet known. But Fire Capt. Daniel Sutter says the initial suspicion is that the transformer caught fire Tuesday for an unknown reason.

Several hundred people were evacuated from the 36-story One US Bank Plaza building after explosions occurred in the street outside just before 5 p.m. No injuries were reported.

The blaze sent fireballs and thick black smoke shooting from the street.

The evacuated building is across from the St. Louis Convention Center. Construction work has been going on in the area for a couple of months.

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