The U.S. air traffic controllers union on Monday told its members to keep working during the government shutdown, as Transportation Sec. Sean Duffy warned that air services may be affected the longer the shutdown lasts.

The U.S. air traffic controllers union on Monday told its members to keep working during the government shutdown, as Transportation Sec. Sean Duffy warned that air services may be…

Transportation Secretary Sean Duffy said the government shutdown is adding stress to already overworked and understaffed air traffic controllers.

Sean Duffy had a warning for air traffic controllers who "don’t show up to work" during the shutdown.