Several people were taken into custody at Florida’s Fort Lauderdale-Hollywood International Airport late Monday after Spirit Airlines canceled at least seven flights amid ongoing tensions with its pilots over a new collective bargaining agreement, according to reports.

Earlier in the day, the airlines sued Air Line Pilots Association (ALPA) that represents the Spirit’s pilots in federal court and held the pilots responsible for “an unlawful job action” affecting the airline’s operations.

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There were chaotic scenes at the Spirit Airlines terminal with stranded passengers demanding answers and some taking to Twitter to post videos from the airport. One showed seemingly upset passengers gathered at ticket counters while another showed police arresting a passenger.

“All of a sudden, one particular flight got canceled, and a mob ensued up here at the front counter, in front of everyone else who had been waiting in line,” one passenger told WSVN, a local news station, adding that Spirit staff were unable to control the upset passengers.

“At that point, the ticket agents couldn’t handle what was going on, so they called in for the police,” the passenger added.

Another traveler told the news outlet he saw police officers apprehending a woman.

“There was a lady [detained] earlier. She was quite upset and very vocal about her frustrations,” he said. “I see people are very disappointed.”

The problem started Sunday, when the airlines cancelled nine flights. At the time Spirit denied its pilots were going on strike despite having issues over a new collective bargaining agreement.

Following the latest situation at the airport, Spirit issued a statement condemning it.

“We are shocked and saddened to see the videos of what took place at Ft. Lauderdale-Hollywood International Airport this evening. This is a result of unlawful labor activity by some Spirit pilots designed to disrupt Spirit operations for our customers, by canceling multiple flights across our network,” Spirit Airlines spokesman Paul Berry told International Business Times, in an emailed statement.

“These pilots have put their quest for a new contract ahead of getting customers to their destinations and the safety of their fellow Spirit Team Members. It is for this reason, Spirit has filed suit in Federal Court to protect our customers' future travel,” Berry added.

Due to the rift between the company and its pilots, the airline had canceled 300 flights in the past seven days affecting the travel plans of over 20,000 customers, according to a copy of the lawsuit provided to IBT by Spirit.

“On this past Sunday, May 7 alone, Spirit was forced to cancel 81 flights due to pilot unavailability, equaling approximately 17 percent of its scheduled flying for the day,” the airline alleged in the lawsuit.

“We are disappointed that ALPA has decided to engage in this unlawful slowdown,” Berry said.  “This has led to canceled flights and prevented our customers from taking their planned travel, all for the sole purpose of influencing current labor negotiations. So we reluctantly filed this suit to protect our customers’ and our operations.”

However, ALPA denied the allegations in a statement to CBS News: "The Air Line Pilots Association, Int'l and the Spirit pilot group it represents are not engaged in a job action. Rather, ALPA and the Spirit pilots are continuing to do everything possible to help restore the company's operations, which have experienced significant problems over the past several days.”

“While we will continue these efforts, we will actively defend the association, its officers and its member pilots against the unwarranted and counterproductive legal action brought this evening by Spirit Airlines," ALPA said.