Flight delays persist at Newark airport

Flight delays could persist into the evening at Newark Liberty International Airport after the control tower was evacuated for an hour due to a report of smoke in an elevator shaft.

Flights couldn't take off or head for the airport for an hour after smoke was reported at 12:44 p.m. Tuesday.

The Federal Aviation Administration says the tower was evacuated by 1:05 p.m. and controllers managed air traffic from an alternate site.

A "ground stop" was in effect for an hour, during which no flights were allowed to take off from or head to Newark.

Controllers returned to the tower at 2 p.m. However, the FAA says they're operating under a "ground delay" that limits the number of flights to safely manage arrivals and departures until 8 p.m.

Officials haven't determined what caused the smoke.