U.S. officials said Tuesday they have referred 22 more cases involving unruly passengers on airline flights to the FBI for possible criminal charges.

The allegations include sexually assaulting female passengers, attacking flight attendants, trying to break into the cockpit, making terror threats, and smoking in airplane lavatories.

The Federal Aviation Administration said the incidents happened as far back as late 2021 and as recently as April of this year.

The FAA can seek fines of up to $37,000 against unruly passengers, but it lacks authority to file criminal charges; that is why the agency refers some cases to the FBI.

Reports of passengers acting up on flights peaked in 2021, with many of the roughly 6,000 incidents involving anger over a since-dropped mask requirement. The number dropped under 2,500 last year and under 1,200 so far this year.

Revenue fell at UPS in the second quarter and it lowered its full-year revenue expectations by $4 billion as package volumes declined and the delivery company came to a tentative labor contract late last month with its 340,000 unionized workers.

Package volume has been in decline for all shippers and fell significantly for UPS during the quarter.

Domestic revenue slid 6.9% as average daily package volume fell 9.9%. The company offset that decline somewhat, however, booking a 3.3% increase in revenue per piece.

CEO Carol Tome said during the company’s conference call that union negotiations impacted its package volume the deeper into talks that they got.

“We expected negotiations with the Teamsters to be late and loud and they were,” Tome said. “As the noise level increased throughout the second quarter, we experienced more volume diversion than we anticipated.”