Authorities have identified her as 41-year-old Danna Eady of Auberry.
The Fresno County Sheriff's Office says the crash happened around 1:50 p.m. Saturday near the Sierra Sky Park Airport on Blythe Avenue.
Multiple agencies, including the Fresno Police, the Fresno Fire Department, the Fresno County Sheriff's Office and the North Central Fire Department, responded to the crash.
When first responders arrived, they found the plane on fire atop the bluff of the San Joaquin River.
Firefighters immediately worked to extinguish the flames and prevent the fire from spreading to nearby homes.
Four people were aboard the plane. Two adults, a man and Eady, were taken to the hospital for their critical injuries. The two children were pronounced dead at the scene.
Eady later died at the hospital.
Officials say the three other victims' identities and their relationship to one another are unknown at this time.
Fresno City Councilmember Mike Karbassi released the following statement on Facebook:
Adventures in Sky Aviation also released a statement on Facebook saying in part:
We want to reassure our students, members, families, and friends that Adventures in Sky Aviation was not involved in this accident. None of our aircraft, instructors, or students were involved.
We have no further information regarding the circumstances of the accident and will not speculate or comment further. The FAA and NTSB are the appropriate authorities conducting the investigation, and any official information regarding the accident should come from them.
Power was briefly knocked out for nearby residents during the time of the crash but has since been restored, according to PG&E's outage map.
The National Transportation Safety Board is taking over the investigation. The Fresno County Sheriff's has established a perimeter to preserve the crash site for the federal investigation.
This is a developing story. Stay with Action News for updates.