Airplane passengers are behaving badly.

On Monday, the U.S. Federal Aviation Administration said that airlines have generated 1,300 unruly-passenger reports since February. That’s a sky-high number. According to NBC News, “In a typical year, the transportation agency sees 100 to 150 formal cases of bad passenger behavior.”

Keep in mind, the number of airline passengers is still dramatically below the pre-pandemic norm.

So what’s behind the drastic increase in agitators?

Earlier this year, the FAA said “these incidents have stemmed both from passengers’ refusals to wear masks and from recent violence at the U.S. Capitol.”

Earlier this month, for example, an Alaska State Senator was banned from Alaska Airlines for repeatedly refusing to comply with the mask mandate. Meanwhile, Delta Air Lines has barred more than 1,200 passengers for failing to wear masks.

Two days after the deadly insurrection at the U.S. Capitol, an American Airlines flight was nearly diverted after disruptive passengers were chanting “USA” and “Fight For Trump,” according to videos of the incident.

In January, the FAA announced a “zero-tolerance policy” for unruly passengers including “fines of up to $35,000 and imprisonment.”

According to CNN, “at least four fines have been imposed on passengers under the stricter enforcement policy, the largest being for $27,500.”

NBC News lays out some of the more galling episodes:

Sara Nelson, president of the Association of Flight Attendants union, said airline employees have reported a wide range of troubling incidents.

“What we have seen on our planes is flight attendants being physically assaulted, pushed, choked,” Nelson said. “We have a passenger urinate. We had a passenger spit into the mouth of a child on board.

“These are some of the things that we have been dealing with,” Nelson said, adding that the physical and verbal abuse that flight attendants have allegedly experienced this year has been “way off the charts” compared to the last 20 years.