Dozens of flights were canceled or delayed Saturday at Amsterdam's Schiphol Airport as a group of KLM's baggage handlers went on strike on one of the busiest days of the year at a major aviation hub to protest working conditions and staff shortages, AP reported.

The KLM luggage handlers' strike coincided with the first day of school holidays, and families went on vacation for the first time since coronavirus-related restrictions were lifted in many countries.

KLM said in a statement that the strike "has far-reaching implications for our customers and other colleagues during this stressful time. The carrier said it was negotiating with the striking staff.

Schiphol warned on its website of flight delays and cancellations and advised passengers to contact their airline for flight information.