'Said he'd be right back': A 15-year-old left home on Halloween. An hour later, he was dead.

OKLAHOMA CITY —

Four days ago, a 15-year-old was shot and killed in downtown Oklahoma City, leaving his grieving family behind.

Diego Esparza-Avila was a sweet kid who enjoyed going out and having fun, his parents said. On Halloween, he was shot while he was in a car.

Police have yet to identify the shooter.

"My son didn't deserve to die like this," Diego's father said, in an interview that sister station KOCO translated to English.

His parents agreed to speak to KOCO on the condition of anonymity.

The family was preparing to celebrate his brother's birthday when Diego left the house. His mother had urged him to stay.

He was shot at about 7:30 p.m. He left the house just one hour prior.

"My wife said, 'Son don't leave. Where are you going? We're going to cut the cake.' He said he'd