For the second day in a row, New Hampshire fire officials were called to a shopping plaza in Manchester where elevated carbon monoxide levels were detected.
Authorities were called to 1525 S Willow St. on Friday morning, the same place they responded to on Thursday afternoon, for high levels of CO.
About a dozen people were evaluated on the scene for possible exposure to CO but nobody was taken to a hospital. The scene was cleared by 11:45 a.m.
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District Chief Mike Gamache said the source of the CO was a disabled rooftop HVAC unit.
Repair crews were called to fix the broken unit.