A child died Thursday evening after having a medical emergency — possibly cardiac arrest — on a flight bound for Seattle from Los Angeles, according to Los Angeles officials.

Delta flight 2423 turned around near Santa Barbara and returned to Los Angeles International Airport almost an hour after its 5 p.m. takeoff, according to flight-tracking service FlightAware.

Paramedics at the gate “furiously worked to save her life,” according to a statement from the Los Angeles Fire Department.

“Sadly, all efforts were futile and the child was beyond medical help,” said Margaret Stewart of LAFD. The girl was pronounced dead at the scene.

The Los Angeles County coroner’s office identified the girl as 10-year-old Janice Xu of West Vancouver, Canada.

The Los Angeles Police Department is investigating, but officials say there are no immediate indications of anything suspicious. The Los Angeles County coroner’s office will determine the official cause of death.

Seattle Times staff reporter Asia Fields contributed to this report, which also uses information from The Los Angeles Times.