MIAMI -

A 16-year-old boy was shot and killed by a police officer Wednesday night in the Overtown section of Miami, according to investigators.

An undercover robbery investigation near Northwest Fourth Avenue and 17th Street resulted in the shooting.

An undercover detective wore a food deliveryman's uniform in Wednesday night's operation.

"They were in a Chinese delivery van, and there was a young male going towards them, and I heard gunshots after that," said a resident who did not want to be identified.

The sound of shattering glass through her front living room window was enough to send the woman ducking for cover.

"I thought someone was shooting at me," she said. "I fell on my right hand and my right hip."

Police identified the person who was shot as 16-year-old Joel Lee Johnson.

A source close to the investigation told Local 10 that Johnson was armed.

Johnson's family showed up at Miami Police Headquarters Thursday to demand answers.

"He's not a violent kid. He doesn't get in any trouble. He doesn't have a criminal record. They won't tell us anything. They just say it's an open investigation and that's it," said Lisa Singletary, Johnson's aunt.

"What do you want to know about what happened last night?" Local 10's Terrell Forney asked Joe Johnson, the teen's father.

"Everything," he said. "They aren't telling us anything, man."

"We'll get it handled through a lawyer. We'll get somebody to find out what we can't find out," said another family member.

This operation happened just three blocks away from another police-involved shooting last month when a rookie police officer shot and killed a man during a traffic stop.

Over the last few days, police have been saturating the area in an operation called "Take Back Our Streets" in an effort to curb crime.

"We have a lot of residents that are concerned about crime in this area,? said Miami Mayor Tomas Regalado. "We are here to tell the residents that there is going to be a full investigation and the police department is doing their work."

?If you were at the press conference yesterday, you must have heard me say that there were some operations that were being worked that I could not give any details and a lot of them were undercover operations,? said Miami Police Chief Miguel Exposito.