Construction workers caused a small street fire in the South Loop, drawing a hazardous materials response Thursday night, fire officials said.
About 9 p.m., workers drilling for soil samples hit an object on Wells Streetbetween Quincy and Adams, according to a Chicago Fire Department spokesman.
The accident caused some power outages downtown, fire officials said.
The HazMat was secured about 10:45 p.m., and no one was hurt.
Wells remained closed as officials investigate the cause.
