Are international thieves exploiting tourist visas to attack the homes of professional athletes?

North America’s top sports leagues have warned their players of a growing threat from high-tech organized burglary gangs whose preferred tools are passports, cutting-edge technology and a 90-day calendar.

The NBA memo, citing FBI intelligence, specifically linked the crimes to “transnational South American theft groups” that target “professional athletes and other high net worth individuals.” These groups are known for using “advanced techniques” such as pre-surveillance, drones, signal jammers and other cutting-edge technologies. The NFL highlighted the risks posed by so-called “organized and skilled burglary groups” that target wealthy athletes.

While the warnings did not name the victims, they were issued after the homes of athletes including Kansas City Chiefs stars Patrick Mahomes and Travis Kelce and Milwaukee Bucks forward Bobby Portis were recently broken into . The tactics described in the memos bear striking similarities to a wave of burglaries targeting wealthy residents of Southern California.

Federal and local officials in Los Angeles and Orange County have reported an increase in burglaries by so-called “burglar tourists” – criminals from Central and South America who enter the United States legally on a 90-day tourist visa authorization under the Electronic System for Travel authorization (ESTA). But instead of packing swimsuits and sunscreen, police said these people were armed with disguises, video devices, trail cameras and Wi-Fi jammers. They target wealthy neighborhoods and gated communities before moving on to avoid detection.

These “burglar tourists” have been in operation for at least five years, but their activity has recently intensified as information about addresses and even images of properties become more accessible.

“Transnational gangs may not know everything about the house they are breaking into,” LAPD Detective Chief Alan Hamilton told NBC News on Friday. “But there is always the possibility that these suspects know who they are and are monitoring the athletes’ social media and movements.”

Minnesota Timberwolves guard Mike Conley’s home was also burglarized in September while he attended an NFL game, the Minnesota Star Tribune reported.

Portis posted on Instagram on November 3 that his “valuable possessions” had been stolen from his home during his team’s game the previous day.

Kelce and Mahomes’ Kansas City homes were broken into separately for hours in October. The burglars stole $20,000 in cash and caused $1,000 in damage to Kelce’s home, according to a police report obtained by Kansas City NBC affiliate KSHB.

Mahomes called the ordeal “frustrating” and “disappointing.”

This trend has spread to other cities such as Chicago, Houston and Dallas. “Law enforcement has long recognized this pattern of crime in the Midwest,” Hamilton said. “They weren’t immune to that.”

Law enforcement agencies from coast to coast, including the FBI, have been tracking these criminal networks for years, with suspects linked to South American gangs emerging in almost every state, Hamilton said.

“It’s completely military technology,” Orange County District Attorney Todd Spitzer told NBC News over the summer. “The people we arrested here in Orange County have criminal records from the country of Chile.”

As law enforcement agencies in Southern California make progress in reducing these crimes, they may move more of these operations to other regions of the country.

The NBA and NFL urged players to take preventive measures such as activating alarm systems and surveillance cameras, securing valuables in safes and avoiding excessive social media exposure.

“The FBI reported that in most incidents, the homes had alarm systems that were not activated,” said the NBA memo, obtained by NBC News on Friday. “The FBI also reported that the homes were all unoccupied and in most cases no dogs were present.”