BALTIMORE — The mysterious 2017 murder of an off-duty DC police officer has been solved by a cold case squad in Baltimore, according to police and prosecutors.
Authorities there announced charges against 24-year-old Dion Thompson of Baltimore, who is currently serving a federal prison sentence in New Jersey.
Detectives wrote in court documents that Thompson confessed to the murder of 40-year-old Metropolitan Police Sergeant Tony Anthony Mason, Jr. after they were led to the suspect by a second hand witness who came forward with information about the case.
Thompson was an 18-year-old neighborhood drug dealer and gang leader. On November 4, 2017, Mason and a woman he was dating were ambushed while sitting in a car talking after an evening out that included shopping at Walmart.
The incident happened in the 2800-block of Elgin St. in Baltimore at about 12:45 a.m.
According to investigators, Thompson and two other accomplices carried out a drive-by shooting on Mason's car because Thompson was suspicious that the strangers parked near his drug territory were rivals plotting revenge.
Thompson had no idea that Mason was an off-duty DC police officer until he saw a report of the incident on the news.
Mason's companion was wounded in the shooting and survived.
In court documents, investigators wrote that Thompson was the leader of a gang called "The Slickest Ones" or TSO.
They said he teamed up with accomplices going by the street names of "Man-man" and "Chub" to carry out the shooting.
Police said 16 shots were fired by two handguns.
One of the accomplices has since been killed. Another remains a suspect in the officer's murder.
Metropolitan Police Chief Pamela Smith called the closure of the case "heartbreaking."
She applauded Baltimore Police and prosecutors for creating a cold case unit that continued to pursue leads years after the crime.
“I hope this development brings some measure of closure to a life that was ended much too soon."
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