The four people injured in an apparent gas leak Monday at Los Angeles International Airport were all airport employees, according to an update from the Los Angeles Fire Department.
The condition of the most critically ill victim has been upgraded from serious to critical following the incident.
A woman and three men were working in or near a utility room “when a popping sound was heard and an apparent release of carbon dioxide vapor occurred,” the LAFD report said.
The most seriously injured man, described as being in his 50s, was found not breathing and without a pulse in the utility room. CPR was immediately performed and advanced life support was administered by emergency responders as he was transported to a nearby hospital, the Fire Department said.
“LAFD Hazardous Materials experts carefully examined the area with sophisticated instrumentation and discovered only traces of carbon dioxide remaining inside the utility room,” the LAFD said.
Portable fans are used to further ventilate the immediate area.
The incident took place in Terminal 8 near the baggage area. The terminal was cleared of passengers after the incident. The area was reopened around 1 p.m. ET (10 a.m. PT), according to a tweet from LAX Airport.
The Federal Aviation Administration’s ground stop for United Airlines’ arrival was also lifted, the airport said.
All other terminals and flights were operating normally, according to a tweet from LAX airport.
“Check your flight status directly with the airline for the best information,” the airport wrote earlier Monday.
United told CNN it was “temporarily consolidating” its operations at Terminal 7 and contacting affected customers with new departure time and gate information.
Passengers going through security bound for Terminal 8 were held in Terminal 7 after screening, Transportation Security Administration spokeswoman Lori Dankers said earlier Monday.
Dankers said all TSA employees are fine and the incident did not involve a TSA checkpoint.
CNN’s Marnie Hunter contributed to this report.
