Johnson was riding his bike at South 21st Street and Cutting Boulevard at about 3:45 p.m. when he was killed in a drive-by shooting, Richmond police Sgt. Bisa French said.
Officers received reports of gunfire from the city's ShotSpotter system and found Johnson.
A white four-door Buick sedan was seen leaving the area after the shooting, French said.
As of this morning, no suspects had been identified and no arrests had been made in the case, French said.