INDIANAPOLIS (AP) — A man died Wednesday, two days after a fire at an Indianapolis apartment left him unconscious and four children ages 1, 3, 12 and 14 in critical condition, a battalion chief said.

Indianapolis firefighters performed CPR on the five victims and transported them to hospitals late Monday, but the man died early Wednesday morning, Battalion Chief Rita Reith said.

The children, who suffered cardiac arrest, remained in critical but stable condition Wednesday at Riley Hospital for Children, 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.

Burning couches can emit dangerous chemicals, and the victims may have been sleeping while the fire burned, she said.

“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,” Reith said.

The 28-year-old man was 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.

The exact cause of the fire remained under investigation, Reith said.