CHICAGO (NewsNation Now) — Amid a rise in violent encounters with unruly passengers on flights, some flight attendants may be getting some training in hand-to-hand combat.

Most of the altercations arise from passengers refusing to comply with federal mask rules. 

“Those incidents…are the highest and most concentrated number that we’ve ever seen — over 3,000. Over 1,900 of those 3,000 were because people refuse to wear masks,” according to travel expert Peter Greenberg.

Greenberg says that aside from tension surrounding the pandemic, alcohol has also been a contributing factor for the violence.

“Here’s the interesting development, in a major part of those cases, what was the contributing factor? Alcohol. So, you have passengers drunk, already on the plane, and at altitude, gee, what can go wrong? Well, everything can go wrong,” said Greenberg.

Andrew Feldman, a spokesperson for the Association of Flight Attendants says in addition to the day-to-day work of flight attendants, breaking up fights has, unfortunately, become another part of their job. He says training in taking down an unruly passenger started after the terror attacks of 9/11.

“We actually think [self-defense training] should be mandatory right now,” Feldman told NewsNationNow.com “They’re voluntary, but we do think they should be mandatory. And look, they’re coming back right at the right time because we are seeing unprecedented levels of unruly passengers in the air.”

Self-defense expert Jennifer Cassetta says hand-to-hand combat is definitely an option, but should not be the first.

“Practicing situational awareness, being able to set boundaries and communicate them powerfully, de-escalate — if possible. Then the physical self-defense comes in,” said Cassetta.