Elderly residents – some in wheelchairs and some dependent on oxygen tanks – were blinded by deadly smoke as they tried to escape an assisted-living facility in Fall River, Massachusetts, which caught fire Sunday evening.

Assisted living centers are rare in Mass, but many families still don’t know what they offer — or what they don’t.

According to Fire Chief Jeffrey Bacon, the blaze started in a room on the second floor on the east side of the Gabriel House building, but details about the exact origin and cause are under investigation.