Two of the responding firefighters were killed Monday by at least one unidentified shooter. (Creative Commons)

Two of the firefighters were killed, while the other two lie in critical condition.

According to CBS News, police were unable to say how many shooters were responsible. Monroe County Sheriff Patrick O'Flynn said there was not active shooter on the scene following the incident.

Meanwhile, the blaze is still going. Officials have decided to let it burn because the scene is not secure. Three houses and one vehicle are in flames. 

It's the latest incident of gun violence to make national headlines, and the second year in a row Rochester has seen acts of serious arson involving homicide. Last year, a 15-year-old boy set his house on fire, killing his father and two brothers. CBS News reported he is being prosecuted as an adult.

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