LIVERMORE — The security guard at a local poker hall has been charged with stealing a $100,000 diamond ring that a high roller accidentally dropped on the floor.

The victim reported that he brought the ring to the Parkwest Casino in Livermore because he wanted to show it to a friend who liked rings, but that it likely dropped from his coat when he stood up. The ring box was discovered by a dealer who turned it over to a security guard, authorities said.

That’s when the crime allegedly took place. The guard checked around and snuck the ring from the box into his pocket, but apparently didn’t count on security cameras catching the whole thing. When the ring was reported stolen police reviewed the footage and identified the culprit as a 49-year-old security guard who lives in Stockton, authorities said.

The suspect confessed and told police exactly where to find the ring, which they were able to do, authorities said.

While it is rare for police to investigate crimes committed by local casino staff, it is not unheard of, and the investigations always seem to involve large amounts of money. In 2020, two people — including a Parkwest card dealer — pleaded guilty to a $4 million scheme involving cheating at baccarat tables. The guilty pleas were reached even after a judge quashed one of several search warrants based on a state law enforcement agent’s failure to comply with regulations, court records show.

In 2022, Livermore police investigated allegations a blackjack dealer was embezzling thousands of dollars worth of high-value poker chips at the Livermore Casino. When questioned, she confessed but said she was doing it to help out a cousin who was in dire financial straights, according to court records.

Police wanted to know what the woman was getting in return for risking her job and criminal charges. She had her answer ready.

“Hugs,” she allegedly told them.