The cruise line known for its “fun ships” is warning passengers not to get out of hand.

In a recent update to its cruise ticket contract, Carnival Cruise Line said unruly guests could be slapped with a $500 fine — and forced to reimburse expenses that result if they are detained or made to disembark early.

“Consistent with our commitment to safety, disruptive behavior will not be tolerated and any guest whose conduct affects the comfort, enjoyment, safety or well-being of other guests or crew will be detained onboard and/or disembarked at their own expense and will [be] banned from sailing on Carnival in the future,” the contract says.

The update follows the introduction of a curfew for passengers under 18 last month. Unless accompanied by an adult in their group who is 21 or older — or unless participating in an official ship-run youth activity — underage guests could be required to leave all public areas by 1 a.m. Travelers on Carnival will be asked to acknowledge the code of conduct when they check in online in the near future.

Though better known for their buffets, dance contests and sunbathing, several Carnival cruises have made headlines in recent months when large fights broke out. In September, Carnival Sunrise was ending a Western Caribbean trip when passengers started fighting on the pool deck. Another brawl broke out near some stairs on the Jacksonville-based Carnival Elation in July, according to local media. And the Carnival Magic was returning to New York when a giant fight started in a nightclub in June, requiring the Coast Guard to escort the ship, NBC New York reported.

Planes, too, have seen a rise in disruptive behavior by passengers in recent years, sometimes leading to violence. According to the Federal Aviation Administration, there have been 2,011 reports of unruly passengers in 2022 as of earlier this week, with 721 investigations started.

“Cruise ships, like virtually all parts of travel and tourism — including airlines, amusement parks, sporting events and camping facilities — are experiencing an increase in more agitated behavior by a small number of guests,” Carnival said in a statement. “Our commitment to the health, safety and security of all of our guests and team members is being demonstrated through the implementation of various measures to assure that our ships remain a welcoming, family-friendly place, including a revised guest code of conduct.”