NEW YORK (CBSNewYork) – At least six people were hurt when a pair of manhole fires broke out Wednesday in Manhattan.

The fires started around 9:45 a.m. on East 32nd Street between Madison and Fifth avenues in Midtown. The scene became a 2-alarm fire after elevated of carbon monoxide were detected in Midtown.

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FDNY officials say the incident began with four to five manhole fires followed by a flash explosion in a building at 6 East 32nd St., an 11-floor commercial office building.

Four firefighters and one building worker suffered minor injuries.

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East 32nd Street was shut down between Madison and Fifth, while Madison was closed between 31st and 34th
strees. M4 and Q32 buses were detoured.

Two building were being evacuated as FDNY crews went building to building, checking every apartment to make sure people got out safely.

FDNY officials say the fire started in electrical wires, but the exact cause was still under investigation.

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Check back with for more on this developing story and watch streaming on CBSN New York.