SANTA ANA, Calif.—A would-be robber who fatally stabbed a man in Tustin during a failed heist in 2019 was sentenced to 25 years to life in prison.

Miguel Angel Orellana, 23, of Anaheim, was sentenced Feb. 2 for the Dec. 9, 2019, killing of 62-year-old David Nakaki.

According to Tustin police and the District Attorney’s Office, Mr. Nakaki was out for a walk in his neighborhood when Mr. Orellana approached him and demanded money in the area of Prospect Avenue and Norwalk Park Place.

When Mr. Nakaki told Mr. Orellana he didn’t have any money, the young man stabbed the older man, prosecutors said.

Mr. Orellana then got back into a car being driven by his girlfriend, then- 25-year-old Erika Pineda of Santa Ana, authorities said. Ms. Pineda is awaiting trial on charges of conspiracy to commit a robbery and being an accessory after the fact. She faces up to five years and eight months in prison, and is due for a pretrial hearing on April 19, according to the District Attorney’s Office.

Mr. Orellana pleaded guilty to first-degree murder and admitted the personal use of a knife in the crime.

“A man who was simply out for a nighttime walk in his own neighborhood was callously murdered when he said he left his wallet at home,” District Attorney Todd Spitzer said in a statement. “This is as cold-hearted and ruthless as a homicide case can be. Instead of walking away, this defendant decided to take someone’s life and leave a family with a lifetime of grief and mourning because of a reckless act.”