Medford fire investigators say they can't determine what caused an east Medford apartment fire that killed a 5-year-old girl and damaged two units in November.

Medford Fire-Rescue put out a press release Thursday saying the Cedar Tree Apartments fire, which happened in the early-morning hours of Nov. 2, started in the front room of a unit where 53-year-old Tonya Johnson lived. But while they have determined the starting place, they couldn't determine the ignition source. In order to assign an official cause, the possibility of other ignition sources must first be eliminated, the press release said.

No one was in Johnson's apartment at the time of the fire. In a strange twist, she had been struck by a 1998 Toyota Camry and seriously injured while crossing South Pacific Highway near Lowry Lane the night before the fire broke out. Police previously said their investigation pointed to Johnson running out in front of the vehicle, but police don’t know why.

Johnson was listed in serious condition for months before a Medford police detective and fire investigator were able to speak with her, fire officials reported.

When she woke up, Johnson was unable to recall any events about the motor vehicle accident or the fire, the release said.

“Investigators believe Johnson was the only occupant living at the apartment when the fire took place. Pending any additional information, (Medford police) is suspending their portion of the investigation.”

The fire broke out at 5:35 a.m. at the apartments, located at 2300 E. Barnett Road. Firefighters upgraded the blaze to a three-alarm fire, as Johnson’s apartment was fully involved and the flames had begun to spread to a second unit on the same floor, blocking a stairwell exit used by both units. A man had to toss his 2-1/2-year-old and 9-month-old children from the balcony into the arms of firefighters below, then had to jump himself, injuring his leg. When firefighters entered the second apartment, they found 5-year-old Olivia Chapman unconscious, and her 3-year-old sister, who was hiding under a bed. The girls’ mother made it out without injury.

Olivia suffered severe burns and died in a Portland hospital less than two weeks later.

Police and fire officials could not immediately be reached for additional comment.

Anyone with new information about the fire is asked to call Medford police at 541-774-2230.

Reach reporter Ryan Pfeil at rpfeil@rosebudmedia.com or 541-776-4468.