The shortage on Monday forced the F.A.A. to delay flights to the busy airport for up to nearly seven hours, the latest problem to plague the airport.

As few as three air traffic controllers were working at Newark Liberty International Airport Monday evening, according to a published report. That’s 11 fewer than the targeted amount for that time period, The New York Times reported.

Technology and staffing problems have plagued the airport, one of the nation’s busiest hubs. Officials say they are trying to resolve the issues, but concerns remain.