Two sisters were killed in a fire that destroyed six homes in Cumberland County late Thursday night.

The blaze in Millville was reported at around 11 p.m. Wednesday, but firefighters' initial efforts were hampered because a nearby hydrant wasn't working, Millville Fire Chief John Wettstein said. Crews had to run about 800 feet of hose to another hydrant and nearly that length to a third to combat the blaze, which burned for several hours before it was brought under control.

Two homes were engulfed in flames when firefighters arrived, and the blaze soon spread to a third.

“This is an unimaginable tragedy. My heart is broken for the family who lost two young daughters in this devastating fire, and my prayers are with them and everyone affected—this is a loss that shakes our entire community to the core,” state Sen. Michael Testa wrote in a statement.

About two dozen residents were displaced. One woman said she and her three young children safely escaped their burning home because the fire awoke her boyfriend, who was able to alert them and get them to safety.

The cause of the fire remains under investigation.