A 75-year-old woman who was seriously injured in a single-car crash in Lakeland last Friday has died, the Polk County Sheriff's Office said.

Investigators believe a medical problem may have caused Francis Deaton of Lakeland to black out before she lost control of her Nissan Sentra on Rockridge Road. The car left the road, struck a tree and rolled over.

Deaton was taken by ambulance to Lakeland Regional Medical Center, where she died in recent days.

Investigators said no other vehicles were involved and that impairment, speed and distraction did not appear to be factors in the crash.