(NAPERVILLE) A 12-floor building in west suburban Naperville was evacuated early Monday after receiving calls of a natural gas leak.
Authorities responded to the building in the 2100 block of City Gate Lane about 4:30 a.m., according to a statement from the Naperville Fire Department. The building had elevated readings of natural gas and carbon monoxide.
Officials determined the gas and carbon monoxide were the result of a malfunctioning heating/air conditioning unit on the roof, the statement said.
The natural gas supply was shut off and building ventilated until readings for gas and carbon monoxide reached zero, the statement said.
Occupants were allowed to return to the building. No injuries or illness were reported.