A Phoenix-based flight attendant died during a layover in Denver, the Association of Professional Flight Attendants (APFA) said Sunday.

The association identified the flight attendant as Celinda Levno, who began her career as a flight attendant in 1989.

American Airlines said in a statement that Levno was the "victim of a senseless crime" Saturday night in Denver and the incident is being investigated by Denver law enforcement. The airline did not specify the nature of the crime.