Five children died in a “devastating” house fire, Indiana authorities said.

The fire at the South Bend home was reported at 6:30 p.m. Sunday, Jan. 21, WNDU said. Upon arrival, crews discovered “intense flames” had engulfed both floors of the home, according to the fire department.

Firefighters said they encountered “overwhelming heat and smoke” as they battled the fire from within. They went inside to rescue some of the victims, who were trapped on the second floor.

But five of the people — all children — were pronounced dead after being removed from the home, the fire department said. Their ages were not disclosed as of Monday afternoon.

A survivor was taken to a burn center in Indianapolis, but their age and identity are unknown.

“As we mourn the lives lost, we also extend our deepest sympathies to the families affected by this tragedy,” Gerard Ellis, the assistant chief of fire prevention for the department, said in a news release.

The cause of the fire is under investigation, the fire department said.

Officials said one firefighter was also injured when he “fell through the second floor onto the first floor.” He was taken to the hospital but has since been released and is recovering at home.

“The firefighters of Engine 2, in their unyielding commitment to protect and serve, exhibited a profound disregard for their own safety in the face of extreme danger,” the department said. “Their actions reflect the highest ideals of selflessness and a citizens-first ethos, characteristics emblematic of the bravery inherent in our city’s first responders.”

South Bend is about 95 miles southeast of Chicago.