The NFL’s security division is warning players to be aware of professional burglars targeting the homes of pro athletes.

The Athletic reported Thursday that the NFL sent a memo to teams that outlines the threat.

“The homes of professional athletes across multiple sports leagues have become increasingly targeted for burglaries by organized and skilled groups,” read the memo, which was obtained by The Athletic. “Law enforcement officials have noted these groups appear to exploit team schedules to target athletes’ homes on game days.”

NBC News reported Wednesday that law enforcement is working to figure out whether an international crime syndicate is involved.

The Athletic reported that the memo includes tips for home security and also gives recommendations about the use of social media, such as not posting photos of items that would attract thieves. Players also learned via the memo how homes are targeted and how burglars enter.

Mahomes hasn’t said much about the burglary, other than to call it “disappointing” and “frustrating.”

“I can’t get into too many of the details because the investigation is still ongoing,” he said. “But obviously something that you don’t want to happen to really anybody, but obviously yourself.”

It’s not clear what was stolen from Mahomes’ home in Belton, Mo., during the Oct. 6 incident. But Kelce apparently lost $20,000 in cash in the burglary at his home in Leawood, Kan., the following day when the Chiefs played the New Orleans Saints on “Monday Night Football,” according to a police report.

The burglary at the home of Milwaukee Bucks forward Bobby Portis in River Hills, Wis., occurred Nov. 2 during the Bucks’ home game against the Cleveland Cavaliers, He said the perpetrators “took most of my prized possessions” and is offering a reward for the return of his property.

“Any info that leads to the return of any of my belongings will be rewarded handsomely,” Portis said. “Let me know, thank you.”