WASHINGTON >> The U.S. State Department says it has managed to bring home over 9,000 Americans stranded in 28 countries after the global coronavirus all but closed down many national borders and severely curtailed international flights.

That’s up from a total of over 5,000 from 17 countries a day earlier.

It wasn’t immediately clear how the number jumped by roughly 4,000 in a 24-hour period. Several evacuation flights carrying hundreds of Americans home, many of them back from Latin America, have departed since Monday. Some 13,500 Americans have sought assistance from the State Department in returning home.

Spokeswoman Morgan Ortagus says the State Department “has never before undertaken an evacuation operation of such geographic breadth, scale, and complexity.” She said U.S. embassies and consulates around the world are continuing to try to arrange flights for Americans.

The department has come under criticism from some stranded Americans and lawmakers for not doing enough to help.