JACKSONVILLE, Fla. -

A woman and her three grandchildren are dead after a fire at a Jacksonville mobile home.

The fire tore through a double-wide mobile home late Tuesday afternoon.

Jacksonville Fire and Rescue Department officials said the woman and one child died at the scene. Family members said two other children died a short time later at the hospital.

The children were identified as Richard Fowler, 4, Rachel Fowler, 2, and Janet Fowler, 10 months old.

Robert Pritchard

Robert Pritchard, a 13-year-old riding by on a bicycle, rescued a 6-year-old girl from the fire. She was identified as the kids' sister, Hattie Fowler.

The parents of the children are in jail, so the kids were staying with their grandparents.

Investigators are trying to determine what caused the fire.