Newark Liberty International Airport is facing another FAA-imposed ground delay due to staffing shortages, after a telecommunications issue led to delays on Sunday.

Sean Duffy said it is safe to fly, but major outages such as the ones in Newark could still pose “a risk to life” and must be swiftly resolved.

At times Monday evening, as few as three air traffic controllers per hour were lined up to monitor via radar the planes flying into and out of the airport, the Federal Aviation Administration said.

US Transportation Secretary Sean Duffy said that Newark airport would see “several weeks” of reduced capacity as officials grapple with spiraling delays and safety lapses at one of the country’s busiest hubs.

Similar to last summer, there is currently a nationwide shortage of air traffic controllers, which will “take time” to replenish, according to Transportation Secretary Sean Duffy.

U.S. Secretary of Transportation Sean Duffy is under fire for deflecting blame over the escalating crisis at Newark Liberty International Airport—issues his department has yet to resolve. Critics point to his references to “cracks in the system” nationwide and a so-called “Brand New Air Traffic Control System Plan” that,

Staff shortages and equipment failures at Newark Liberty International Airport have raised safety concerns in recent weeks.