The NBA on Friday circulated a memo urging players to upgrade their home security and consider getting guard dogs following a rash of burglaries targeting professional athletes.

Mike Conley of the Minnesota Timberwolves and Bobby Portis of the Milwaukee Bucks have been victims, as well as NFL stars Travis Kelce and Patrick Mahomes of the Kansas City Chiefs.

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The guidance came in a memo the league sent to teams, a copy of which was obtained by ABC News.

In most of the burglaries, the homes were equipped with alarm systems that were not activated, the memo said.

Besides updating home security systems, the memo urged players to “remove any real estate listings with photos of your home from publicly accessible websites” and to “utilize dogs for home protection.”

The league also advised players to vet contractors who are working at their homes.

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The memo confirms ABC News’ reporting that the FBI suspects many of the burglaries targeting athletes and other luxury homeowners are connected to South America theft groups, which are “well-organized, sophisticated rings that incorporate advanced techniques and technologies, including pre-surveillance, drones and signal jamming devices.”

Police believe the athletes are being targeted based on their game schedules. All of the thefts have occurred while no one is home.

The primary interest is cash as well as items that can be resold on the black market, like jewelry, watches and handbags.