PATERSON, N.J. (CBSNewYork/AP) — A woman and her brother who were injured in a Paterson fire that claimed the life of their grandmother earlier this week have died.

Twenty-three-year-old Alexandra Velarde and 19-year-old Christian Velasquez were removed from life support after doctors harvested their organs on Thursday night.

Their 75-year-old grandmother, who was being treated for cancer, died in the fire.

The blaze broke out just after 6:30 a.m. Wednesday at the intersection of Trenton and Maryland avenues. It took nearly 45 minutes for firefighters to put out the fire, which officials believe started in the living room on the first floor.

Officials said there were no working smoke alarms in the home.

A minister told The Record newspaper the siblings had delayed leaving for Liberty University in Virginia to help their mother. She escaped injury.

A fourth person remains in critical condition.

Three firefighters responding to the blaze were also burned.

The cause of the fire remains under investigation.

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