Photos of female cabin crew lying in the overhead luggage compartments on board a Chinese airline have gone viral on social media.
The images, which were uploaded on the popular chat app WeChat, have been called bullying by netizens.
The post said cabin crew were "forced into lockers by security staff upon completing 30 to 50 hours of service" as part of an "industry ritual".
Kunming Airlines has issued a statement saying it was investigating the matter.
The company said the incident occurred after the crew had completed their duties and that the safety of the flight was not affected.
The airline added that it had never received complaints from its cabin crew.
"The company attaches high importance to this incident and will prevent such things from happening again," the statement said.
Chinese state broadcaster CCTV News reported on its official Facebook page that while many of the female cabin crew members were "annoyed" by the ritual, they still went through it in fear of not being accepted by their senior colleagues.
"Multiple stewardesses have also consistently filed complaints to the company but their requests were ignored and the ritual continued," it said in the Facebook post.
'Behaving like children'
Outrage following the incident was felt on Chinese social media, with many netizens voicing support for the cabin crew.
"Air stewardesses have it hard enough with difficult passengers and irregular flight schedules. Imagine having to deal with additional trouble from colleagues who should clearly know better," said a Weibo user.
"Professionals in the aviation industry? They are behaving like children in high school," remarked another.
Other users raised the possibilities of safety risks as a result of the incident.
"Even if there are no passengers around when such silly rituals take place, it still poses a safety hazard. What happens if their weight were to impact the overhead cabin and cause it to break during an operating flight?" asked Weibo user YuQing7390.