A smoke alarm inside the Waldorf, Maryland, home that went up in flames Sunday morning, killing six people, had been disconnected and had no battery installed.

Six family members, including four young children, were killed in a house fire in Waldorf, Maryland, on Sunday morning, authorities say. The fire is one of the deadliest in the state in recent memory.

A devastating house fire in Charles County has claimed the lives of six people, including four children, marking Maryland’s deadliest residential fire in more than a decade.