(CNN) — Flight delays linked to the ongoing federal government shutdown continue, with this past weekend marking the worst for air traffic control staffing shortages since the shutdown began, according to a CNN analysis of Federal Aviation Administration operations plans.

Between Friday morning and Sunday night, 98 FAA facilities reported a “staffing trigger,” meaning air traffic controllers had to alter operations to keep the airspace safe with fewer people working.

The alterations can include rerouting planes or delaying flights when there are not enough controllers to handle the normal workload.

Air traffic controllers are considered essential staff and must work during the government shutdown, despite not getting paid. Transportation Secretary Sean Duffy said some controllers h

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