Rochester, MN (KROC-AM News) - Residents of a downtown Rochester condominium complex were chased outside Saturday due to a carbon monoxide threat.

The Rochester Fire Dept. was called to 728 1st Ave SW just before 11:00 AM and detected CO in the building's 5th floor area. The entire building was evacuated as a precaution until it was ventilated.

RFD says the 911 call came from a tenant whose CO detector was activated.

RFD suspects the CO came from two large generators that were running outside the building where construction work was taking place.

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