American travel companies are scrambling to reroute cruise ships and take care of tourists to Mexico after violence and chaos erupted in several coastal regions in the country following the killing of a cartel leader.

The U.S. State Department broadened its warning to travelers to shelter in place across multiple regions of Mexico, including the popular tourist hot spots of Cancun, Playa del Carmen, Cozumel, Tulum, Tijuana and Puerto Vallarta.

Violence erupted after the Mexican army killed Jalisco New Generation Cartel leader Nemesio Rubén Oseguera Cervantes. Known as “El Mencho,” he led one of fastest-growing criminal networks in Mexico, notorious for trafficking fentanyl, methamphetamine and cocaine to the United States and staging brazen attacks against government officials who challenged it, The Associated Press reported.

As roads were blockaded with burning vehicles, airlines canceled flights and cruise lines rerouted ships to avoid ports with potential problems.

Carnival Corp. said Princess Cruises’ Royal Princess and Holland America Line’s Zuiderdam were bypassing their planned stops in Puerto Vallarta on Monday. Norwegian Cruise Line said its ship the Norwegian Bliss has canceled its plans to call on Puerto Vallarta on Wednesday.

MSC Cruises USA said sailings to Cozumel and Costa Maya, Mexico, are currently operating as planned, but that shore excursions may be adjusted or canceled.

Though Royal Caribbean said it doesn’t have ships currently in the affected areas, CNBC has learned some of its excursions in Ensenada, Mexico, were affected.

Airbnb told CNBC it had activated its “major disruptive events policy” in Jalisco state and other affected regions. That policy overrides the host’s individual cancellation policy, allowing travelers and hosts to cancel reservations without consequences.

“We are monitoring this situation carefully and are focused on supporting guests and hosts in impacted areas,” an Airbnb spokesperson said.

In a note to investors, Truist travel and leisure analyst Patrick Scholes wrote that Hyatt has the most exposure of the international brands, with 8.5% of its room total coming from Mexico. Marriott has the second-highest exposure, with 3.3% of its overall rooms coming from Mexico.

Typical travel insurance policies often carry exclusions for terrorism, political violence or civil unrest.

Squaremouth, an online marketplace for travel insurance, warned would-be travelers that “the violence in Mexico is now a foreseeable event, or what the insurance industry calls a known event. So tourists can’t buy coverage now in order to cancel their trip.”

However, a Squaremouth spokesperson told CNBC, “If you are heading to Mexico soon, especially during spring break, buying CFAR [cancel for any reason] or IFAR [interruption for any reason] as add-ons is a smart decision given the uncertainty.”

U.S. and Canadian airlines halted flights to Puerto Vallarta and Guadalajara in Mexico after violence broke out in the country in the wake of the Mexican army’s killing of a cartel leader.

The U.S. State Department on Sunday told U.S. citizens to shelter in place, citing “ongoing security operations and related road blockages and criminal activity.”

Air Canada, American Airlines, Delta Air Lines, Southwest Airlines, United Airlines and others canceled flights to Puerto Vallarta, a popular tourist destination on Mexico’s Pacific coast, and to Guadalajara, which is also in the Jalisco state. Airlines waived change fees for affected travelers.

Flights to other major airports in the country, like Mexico City and Cancun, weren’t impacted by the unrest.

Several Mexican states also canceled school on Monday after the country’s army killed Nemesio Rubén Oseguera Cervantes. Known as “El Mencho,” he led one of fastest-growing criminal networks in Mexico, notorious for trafficking fentanyl, methamphetamine and cocaine to the United States and staging brazen attacks against government officials who challenged it, The Associated Press reported.

He was killed during a shoot-out in his home state of Jalisco, AP said.

Airlines routinely suspend service due to unrest and infrastructure problems to avoid having passengers, crews and aircraft stranded.