Brenda Cropper, 66, died at a hospital after being in critical condition all week after the fire erupted on Sunday, officials said.

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 how they differ from other elder care facilities.