By Brian New

DALLAS (CBSDFW.COM) – With the travel mask mandate extended into January, flight crews are bracing for several more months of elevated tensions.

“It feels more stressful for everyone right now,” said Jacki Drolet, who was among the more than a dozen flight attendants who took part in a TSA self-defense training course in Dallas. “It’s definitely a little scary. You just want to be fully prepared if something happens.”

READ MORE: Amber Alert Issued For 12-Year-Old Girl Out Of Converse, Texas

Since the start of the year, the FAA has received 3,988 reports of ‘unruly’ passenger behavior on flights. Nearly 700 of those escalated to the point where a federal investigation was needed. That’s more cases of alleged ‘unruly’ passengers than in the past five years – combined.

Viral videos taken on commercial flights and posted on social media throughout the summer show passengers screaming, physical fights, and other unruly behavior.

READ MORE: COVID-19 Pandemic Has Taken A Toll On Mental Health, Led To More Drug Abuse, CDC Says

The FAA says more than 70% of ‘unruly’ passenger behavior reports stem from passengers not wanting to comply with the federal mask mandate.

The federal travel mask mandate was set to expire September 13th. It has already been pushed back once.

With the continual spread of COVID-19, the TSA said it will extend the mandate through January 18th.

MORE NEWS: US To Deport 'Massive' Number Of Haitian Migrants From Texas Border Town

“They were ready to not wear them, so the fact that we had it extended might make my job even harder now,” said flight attendant Kaldwella Johnson, who was also among the participates at the TSA’s self-defense training class. “It’s just a little worrisome on how angry they’re getting over something so simple.”