The FDNY is investigating three separate fires that broke out on Saturday in the Bronx and which left three people dead and four injured.

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The first blaze occurred at 3:17 a.m. when authorities responded to calls of a fire at a home at 1354 Beach Ave., police said. FDNY personnel extinguished the fire and found a woman in her 60s — whose identity is still pending proper family notification — unconscious and unresponsive in the basement of the home.

Emergency personnel responded and transported the woman to Jacobi Hospital where she was pronounced dead.

Four other individuals were injured as a result of the fire. A 59-year-old man and 68-year-old female were taken to the hospital in critical condition; and an 80-year-old man and 68-year-old man were in stable condition.

About two hours later and just blocks away, autorities responded to a call of another residential fire at a home at 1795 Guion Place.

When FDNY extinguished the fire, they discovered 26-year-old Carlos Villlafane on the second floor of the home, unconscious and unresponsive with severe burns to his body, according to police. Emergency personnel pronounced Villafane dead at the scene.

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The third fatal fire occurred at about 7:45 p.m. at 934 East 228th St. when the FDNY removed a76-year-old man from the basement of the home, authorities said. The victim was pronounced dead at the scene.

The fire marshal will determine the cause of the fires and individual investigations are ongoing.