United Airlines passengers expressed frustration through social media after the airline giant had two separate issues with its computer systems which caused worldwide delays beginning late Thursday. File Photo by Brian Kersey/UPI | License Photo

CHICAGO, Oct. 14 (UPI) -- United Airlines had two separate issues with its computer systems beginning late Thursday that caused worldwide delays.

"As of 3 a.m. ET, the system issue has been resolved. Any delayed flights are resuming and we apologize again for the inconvenience," United Airlines said in a tweet Friday.


United Airlines spokeswoman Maddie King that a "small number of flights" were affected by the glitches over the computer systems. Previously, the airline told NBC News that 63 flights were affected.

One of the issues involved the airline's luggage weighing systems. Some people expressed frustration with United on social media.

"Way to totally not communicate at all United Airlines," one apparent passenger wrote on Twitter. "System was back up for a bit. But we had no pilots. Now we have pilots. But system crashed again."

"What in the world is going on with United Airlines?" another Twitter user wrote. "How does an entire airline's system meltdown?

The one time I decide to give @united a 2nd chance after a 3 year hiatus, they have a nationwide system shutdown.#UnitedAirlines #neveragain — Aditya Narendranath (@AdiNaren) October 14, 2016