Most bank robbers spend weeks or even months plotting how to get access to the cash in a teller’s drawer or, even better, the vault.

Gary Cazarez had that part down cold; he was the cash vault services manager at Key Bank in Anchorage, Alaska.

On Friday, July 29, Mr. Cazarez apparently decided to chuck his job and become a multi-millionaire. It took him 28 minutes.

According to federal court documents, the 26-year-old manager used his position at the bank to gain access to the vault after hours on that Friday night. He borrowed one of the bank’s rolling carts and three empty computer-sized boxes. Once in the vault, he turned the lights off, presumably to blind the surveillance cameras.

Despite the darkness, Cazarez was apparently able to load $4.3 million into the boxes, according to an FBI affidavit. Security cameras at the bank recorded him pushing the cart and boxes out of the bank to his car in the parking lot.

After thoughtfully returning the rolling cart to the cash vault room, Cazarez drove away. At his home, he transferred the stacks of cash into duffle bags and suitcases. Then he purchased an AK-47, a handgun, and ammunition (for $4,000), met up with his girlfriend in Tacoma, Wash., and bought a Ford Fusion, the affidavit says.

By late Monday, Aug. 1, bank officials noticed that Cazarez had not reported for work. More alarming, someone had time locked the vault and they were unable to open it, according to the affidavit.

The couple drove to Tijuana, Mexico, where they ditched the car and boarded a bus to Sonora. Until that point Cazarez’s alleged crime and escape had gone without a serious hitch. Then the bus stopped. All passengers were required to exit the bus, collect their luggage, and proceed through a police checkpoint.

As Cazarez and his girlfriend walked through the line with multiple duffle bags and suitcases, the officials flagged them for special screening, the affidavit says. That’s when Cazarez whispered to his girlfriend that they were in serious trouble.

He was asked to please open his suitcases. The Mexican police discovered the AK-47, the handgun, the ammunition, and $3,769,320 in cash, according to the affidavit.

Meanwhile, back at Key Bank it would take bank officials another half day to open the vault and discover that in addition to their cash vault services manager, a large amount of cash was also missing.

Cazarez is being held in Mexico pending an extradition request from the US government that he be returned to the US to face trial in Alaska.

This week a federal grand jury in Anchorage returned an indictment charging Cazarez with bank theft.

If convicted, he faces up to 30 years in prison and a $1 million fine.