United Airlines bans 2 girls with leggings from flight because they weren't 'properly clothed'

United Airlines is in hot water after a dress code incident on Sunday morning. 

In a series of live tweets, activist Shannon Watts explained that two girls who were wearing leggings were asked by the United Airlines gate agent to either change clothing or not board their flight to Minneapolis. 

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"This behavior is sexist and sexualizes young girls. Not to mention that the families were mortified and inconvenienced," Watts explained on Twitter. 

"As the mother of 4 daughters who live and travel in yoga pants, I'd like to know how many boys @United has penalized for the same reason. Their father, who was allowed to board with no issue, was wearing shorts," she wrote. 

Another girl in grey leggings was allowed to fly after changing into a dress, according to Watt's tweets

After a large amount of backlash from Twitter users, United Airlines responded to angry inquiries online, citing a dress code that appears in their "Contract of Carriage" that allows them to "refuse passengers who are not properly clothed." 

"Casual attire is allowed as long as it looks neat and is in good taste for the local environment," the airlines also tweeted.

The internet was outraged, both over United's actions and its public response to the controversy. 

Mashable has reached out to United Airlines for comment and will update this post accordingly. 

UPDATE: March 26, 2017, 2:14 p.m. EDT The two girls were United Airlines "pass riders," defined by the company as "United employees or their eligible dependents standing by on a space-available basis." 

There is a separate dress code for pass riders, unrelated to United Airlines previous citations of the "Contract of Carriage," that remains "internal policy" and will not be released, according to a statement made to NBC's Colorado affiliate, 9 News.

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