People are freaking out that United told women they couldn't wear leggings on a flight - here's what really happened

United Airlines refused to let two women board a flight on Sunday because they were wearing leggings, and people on Twitter are outraged.

The gate agent on Flight 215 from Denver to Minneapolis wouldn't let women in leggings on the plane, so one girl reportedly put a dress on over hers before boarding.

Two other passengers weren't let on the plane. But a company spokesperson said it was because they were pass holders using a United employee's flight benefits.

Employees - and friends or family flying on their passes - have to adhere to a dress code since they are representing the airline and its employees when they fly.

Those women were asked to fix their dress code violation, and that they would be put on the next flight with space once they did, the spokesperson told Business Insider.

The backlash began when Shannon Watts, a gun control activist with over 32,000 Twitter followers, tweeted that she witnessed the incident, tagging United.

The airline tweeted back, citing its contract passengers agree to when buying a ticket that gate agents "have the right to refuse transport for passengers who are barefoot or not properly clothed."

United also cited its "dress code for pass travelers" in its responses to Watts on Twitter.

But the outrage online was swift. A Twitter Moment sums up the conflict:

One Twitter user dug up a tweet United posted in June 2016 of a woman in leggings doing a yoga pose in the airport:

Delta Airlines even threw some shade - though it was unclear whether it was intentional or not - to a passenger who thanked the airline within Watts' main thread with United:

Benjamin Zhang contributed reporting.