Updated

Tens of thousands of U.S. college students are flooding into the Mexican city of Cancun, where officials have stepped up patrols of marines, soldiers and special tourist police in zones packed with hotels and bars.

City officials say they expect thousands more visitors than the 25,000 who came to the Caribbean coast resort last year. They say at least part of that increase may be due to people avoiding Pacific Coast cities such as Acapulco, which have been hit by high-profile incidents of criminal violence in recent years.

Cancun tourism director Maximo Garcia Rocha says some major tourist agencies are expecting as many as 43,000 spring breakers, but the major influx was only beginning Friday.

The Cancun Hotel Association says occupancy was at 90 percent citywide.