UPDATE: The City of Chattanooga has made the decision to close for the rest of day.

Mayor Andy Berke said they are closing "out of an abundance of caution for its employees and any visitors."

Early Friday, Chattanooga City Hall was evacuated after reports of a gas leak. The 'all clear' was given.

The building will reopen Monday.

PREVIOUS STORY: Employees at Chattanooga City Hall have returned to work after reports of an early morning gas leak led to the evacuation of the building.

Chattanooga firefighters were called to city hall around 8:00 am after employees called 911 and said they smelled a chemical odor.

"After a brief investigation, it was determined that a subcontractor for the city's stormwater division had been spraying styrene to line the stormwater pipes underground," Chattanooga Fire Department spokesman Bruce Garner said. "The resulting fumes spread through the pipes and into some openings for the pipes underneath city hall."

The fumes are non-toxic and do not put anyone in danger, the department explained.

Garner said the building evacuation was done as a precaution, and no injuries have been reported.

CFD crews are in the process of investigating the possible source.