Firefighters cut gas service to 40 buildings in the Little Village neighborhood after a construction crew broke the gas main.
The main broke Thursday morning around 11 a.m. and prompted a Level 1 Hazardous Materials response from the fire department.
"We are working to assess and repair any damage as quickly as possible," the gas company said in a statement.
The affected area is between Cermak Road and 25th Street, from Kedzie Avenue east to Albany Avenue.
A fire official said that schools in the area won't be affected because they have backup service.
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