The luggage triggered an alarm and required an inspection by TSA and United representatives at about 8:30 a.m., said TSA spokesman Nico Melendez.
United flights were briefly grounded but were released for takeoff at about 8:50 a.m., according to airport spokesman Doug Yakel.
Authorities are not yet saying what was in the baggage and the incident remains under investigation, Melendez said.
