As long lines continue to snarl security checkpoints at U.S. airports amid ongoing staffing shortages, travelers can monitor estimated wait times online before heading out.

Some airports across the U.S. have a very different security setup that most travelers don't know about, and here's how it works when they don't use TSA.

ICE agents assist with TSA wait times and Precheck security lines amid shutdown. Check wait time at DCA, IAD, BWI, CLT and ATL airports in DMV today.

Airports across the U.S. have seen fluctuating wait times in recent days amid the partial government shutdown.

Security lines at TSA checkpoints improved at airports across the country on Monday as TSA officers started receiving back pay following President Trump's executive order. But uncertainty lingers with Congress on recess and still no funding passed for DHS.