Delta Air Lines canceled more than 600 flights on Monday, as the U.S. air carrier continued to struggle to restore operations after last week's global cyber outage, even as other airlines were recovering from the incident.

About 16% of Delta's flights had been canceled as of 7:00 a.m. ET, according to data from FlightAware, out of roughly 1,100 flights to or from the United States overall, the website said.

The issue has stranded thousands of Delta travelers across the United States, with some having to rent cars to drive hundreds of miles while others could have to wait days for new flights or cancel trips altogethe