Passengers crowd around Jeju Air's ticketing counters at Jeju International Airport, July 19, after the budget airline's check-in and booking systems suffered disruptions in the aftermath of a global technical outage. Yonhap

Some low-cost airlines in Korea had fully restored their check-in and booking systems 12 hours after disruptions caused by a global technical outage, which also affected the IT and financial sectors around the globe, the state-run airport operator said Saturday.

Incheon International Airport Corp. said three budget airlines — Jeju Air, Eastar Jet and Air Premia — had recovered their ticketing and booking systems as of 3:30 a.m.

A total of 75 flights were delayed due to the disruptions, according to the airport operator.

The tech outage was caused by a glitch in cybersecurity firm Crowdstrike's software, which caused Microsoft's Windows operating system to crash.

The three airlines use computer systems based on Microsoft's cloud service.

Online game companies here were also affected by the technical outage.

The management of "Black Desert" from Korean game developer Pearl Abyss posted a notice on its website Friday and said it experienced "server instability" due to a "sudden failure" in its equipment.

Other game makers, such as Gravity, the developer of online role-paying game "Ragnarok," said they also suffered disruptions. (Yonhap)