A Las Vegas cab driver got the shock of his life when he found $300,000 cash in a brown paper bag left by a gambler in the back seat of his taxi.

Yellow Checker Star cab driver Gerardo Gamboa picked up the unnamed customer at the Cosmopolitan on Monday morning and took him to Palms Place, receiving a $5 tip for the service. But, Gamboa’s passenger had unknowingly left much more than that.

When the veteran taxi driver arrived at his next stop at the Bellagio, a doorman alerted him to a bag in the back, telling him it was “full of chocolate.”

When he pulled up at a traffic light, Gamboa’s curiosity got the best of him and he decided to peek inside. What he found wasn’t chocolate, but rather $300,000 wrapped in six bundles of $50,000 each. “I told my passenger, ‘You are my witness on this,’ and then I immediately called my dispatcher,” Gamboa told the Las Vegas press.

After the cash was transported safely back to company headquarters, officials contacted the Cosmopolitan, who tracked down the panic-stricken owner after finding a record of a recent $300,000 payout. The owner turned out to be a 28-year-old poker player, whose identity authorities refused to reveal, who was so devastated by the loss that “he wanted to shoot himself in the head,” according to a taxi company official.

In somewhat typical poker player fashion, the man showed up to the office in sweats and a t-shirt to reclaim the money, but wasn’t carrying an ID. “We had to be, as a company, extremely cautious that the right person got the money,” cab firm CEO Bill Shranko said.

“He was grateful. He was very understanding; he wasn’t irritated. To a point, he was irritated, but he wasn’t mad or aggressive or anything,” said Yellow Checker Star Field Operations Manager Joel Willden. “Maybe a little more embarrassed than anything. I mean, he left $300,000 in a cab, but he was an awesome guy.”

After a few hours speaking with the Cosmopolitan and Metro police, officials were able to confirm the man’s identity and handed over the cash to the much relieved poker player. The man asked to meet Gamboa and wanted to shake his hand; he said he planned on giving him a reward and took down his contact information.

The small fortune found in the back seat eclipses anything seen by employees at Yellow Checker Star. “This is the largest amount we have found in my 32 years in this business,” said Shranko. “Recently, we found $9,000, but that’s no longer a big deal.”

Despite finding the potentially life-changing sum of money, running off with the loot never crossed Gamboa’s mind. “Even though I am a poor guy, I don’t need money that doesn’t belong to me,” he said.

For his honesty, his employer has already rewarded him with the title of Driver of the Year, $1,000, and dinner for two at a restaurant.

But from his absent-minded passenger, he’s not expecting to receive anything above his original $5 tip. “If he doesn’t give me anything, that’s OK,” Gamboa said. “I’m not waiting for any kind of return. I just wanted to do the right thing and I appreciate what the company did for me.”

For his part, Gamboa thought the incident was an excellent opportunity to show that Las Vegas taxi drivers aren’t bad people. “I did the right thing, that’s it,” he said. “They call us Sin City. But it’s not. It’s Angel City.”

The near-loss by the gambler highlights the risk of traveling with massive amounts of cash. In a remarkable incident last month, poker pro Eric Riley thwarted two robbery attempts while making his way to the airport carrying $100,000 in cash in a duffel bag.

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