At least 3 people are unaccounted for several hours after the blast , city officials say . The next , he saw pianos flying through the air in the shop where he works as an explosion tore through the building . A woman tells FBI her aunt was among the victims killed . A sinkhole in front of the buildings complicates search efforts . two people were killed in the blast , which leveled At least 3 apartment buildings .
At least 3 people are unaccounted for several hours after the blast , city officials say . A woman tells FBI her aunt was among the victims killed . A sinkhole in front of the buildings complicates search efforts . two people were killed in the blast , which leveled At least 3 apartment buildings .