Officials say a United Airlines flight from Washington DC to San Francisco was diverted to Denver after a passenger got stuck inside the jet's bathroom.
KUSA-TV reported that Denver International Airport spokeswoman Emily Williams says the door to one of the plane's bathrooms would not open, but could not confirm why.
Williams says the flight crew called for assistance and the Denver firefighters helped open the door.
Williams says there were no calls for medical assistance.
KUSA-TV says United Airlines confirmed that someone was in the bathroom.
A passenger posted a video on Twitter of the incident.
"We are reaching out to all customers onboard and the customer in the lavatory to apologise," United Airlines said in a statement.
Toilets often cause problems for airlines, with cases of flights having to turn back due to broken plumbing and other technical issues. Earlier this year a Pakistan Airlines flight from Manchester Airport was delayed after a passenger, searching for the restroom, mistakenly opened the emergency exit, launching the slides.
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