The young boy was killed on Aug. 5 while inside a home on the 200 block of Clay Street with his mother and two other children, police said.
Officers from the Salisbury Police Department responded to a 911 call at approximately 10:30 p.m. and found Colbert suffering from a gunshot wound.
He was pronounced dead at the scene.
The Maryland State Police Homicide Unit, with help from the Salisbury Police Department, is now investigating the case.
The FBI, Maryland State Police, and Crime Solvers of the Eastern Shore are now collectively offering the $25,000 reward for information that helps identify and convict the individual or individuals responsible for the shooting.
Investigators have been interviewing witnesses, canvassing the neighborhood, and processing evidence, officials say; however, no suspect description is available as of Monday, Dec. 2.
Anyone with information is urged to contact Crime Solvers of the Eastern Shore at (410) 548-1776.
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