An Indianapolis apartment fire left a 28-year-old man and four children ages 1, 3, 12 and 14 unconscious, in cardiac arrest and hospitalized in critical condition, authorities said Tuesday.

Indianapolis firefighters performed CPR on the five victims and transported them to hospitals, Battalion Chief Rita Reith said.

The fire started on a couch late Monday in the apartment on the city's far east side and was under control within a minute of firefighters' arrival, Reith said.

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Burning couches can emit dangerous chemicals, she said.

Indiana local

A fire in Indianapolis sent a man and four children into cardiac arrest. (Fox News)

The victims may have been sleeping while the fire burned, Reith said.

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"We are just hoping for the best, and hoping that these little ones and the adults that are in that apartment can survive what they dealt with tonight," she said.

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The 28-year-old is the father of the 1-year-old and 3-year-old girls, WISH-TV reported. The 14-year-old and 12-year-old are boys.