More than 6,000 flights were canceled worldwide over the long Christmas weekend and thousands more were delayed as the highly infectious Omicron variant brings holiday hurt to millions.

According to Flightaware.com, nearly 2,800 flights were scrubbed around the globe on Saturday alone with over 8,000 delays as of 1:30 pm GMT.

On Friday, there were around 2,400 cancellations and 11,000 delays, while Sunday cancellations have already surpassed 1,100.

Pilots, flight attendants and other employees have been calling in sick or having to quarantine after exposure to COVID, forcing Lufthansa, Delta, United Airlines, JetBlue, Alaska Airlines and many other short-staffed carriers to cancel flights during one of the year’s peak travel periods.

The cancellations added to the pandemic frustration for many people eager to reunite with their families over the holidays, after last year’s Christmas was severely curtailed.

Chinese airlines accounted for the highest number of cancellations, with China Eastern scrapping more than 1,000 flights, over 20 percent of its flight plan, on Friday and Saturday and Air China also grounding about 20 percent of its scheduled departures over the period.