Southwest Airlines has updated its preflight emergency briefing and demonstration by advising passengers to report "any unwelcome behavior" to flight attendants.

The effort comes as major airlines have seen an uptick in onboard harassment incidents in recent years and have struggled with how to combat it.

"This change reflects Southwest's commitment to ensuring a safe and welcoming environment at all times for each of our customers and employees," Southwest spokesperson Brian Parrish said in an email to the Washington Post. "Southwest's intention is to remind our customers that flight attendants are a friendly, professional resource for reporting any unwelcome behaviors or conduct during a flight."

According to the airline, once flight attendants are alerted of such behavior, which is not limited to sexual conduct, they will respond using their discretion along established procedures, which can mean seating the passenger who reported it elsewhere, asking the offender to stop the behavior, and — if the conduct requires it — telling the captain, who can request law enforcement assistance when the plane lands.

Southwest says it views passenger safety as an "uncompromising priority." Incidents of sexual assaults on planes have risen in recent years across the country, according to the FBI.

Airlines often have trouble assessing how to deal with each case, from disciplining the perpetrators, to protecting the victims, ensuring other passengers' safety, dealing with the public reaction, and interacting with law enforcement.

In a high-profile incident of sexual assault on a Delta Air Lines flight last summer, kidnapping survivor and author Elizabeth Smart said she was awakened by a man rubbing her inner thigh as she slept. In an interview with CBS This Morning, she recalled the experience bringing her back to the time as a 14-year-old in 2002 being held captive and raped nearly every day for nine months.

“I’ve never been worried, I’ve never felt threatened on an airplane, until now,” she said.

Many airlines say they update their policies regularly to deal with harassment and issues concerning passenger safety, in which incidents are handled on a case-by-case basis.