HONOLULU (KHON2) — On Wednesday, August 24, 2022 a fire broke out in the back of an ambulance and killed a 91-year-old patient and left a 36-year-old paramedic critically injured.

After a months-long investigation, which included an outside investigator that specializes in oxygen-related fires, the Division received a final report of its findings.

Check out more news from around Hawaii

According to Emergency Care Research Institute, they found the origin of the fire to be the portable oxygen cylinder regulator assembly.

ECRI said the possible causes could have been contamination or particulates within the oxygen cylinder.

The exact cause was not able to be determined.

Honolulu Emergency Medical Services continues to send their condolences to the family of the deceased patient.

Get news on the go with KHON 2GO, KHON’s morning podcast, every morning at 8

Paramedic Jeff Wilkinson is recovering at home.