March 4 (UPI) — Five people, including two children, were killed in an early morning house fire in Rockland County, N.Y., authorities said Saturday.

Alan Simon, the mayor of Spring Valley, N.Y., said the fire occurred around 4 a.m. at a home in the town, located about 30 miles north of New York City.

Five other people were reported injured in the blaze.

“Three were found on the second floor in different areas and two were found on the first level, and we believe they were found on the first level due to a collapse on the second floor into the first level,” Rockland County Fire Coordinator Chris Kear told reporters.

One firefighter was also injured in the blaze as rescuers had trouble entering the house.

“With the extent of the fire, the conditions weren’t good. It was impossible,” Kear said, adding that although firefighters were forced to remain outside of the structure as it burned, they succeeded in extinguishing the blaze.

Afterwards, he said, “searches began within the dwelling to look for the individuals that were reported missing.”

The flames were so intense that one man jumped out of a second-story window to escape, WPIX-TV reported.

The cause of the fire is still under investigation.