Dion Thompson has been arrested for his alleged role in the murder of MPD Sgt. Tony Mason, Jr., on Nov. 4, 2017 in the 2800 block of Elgin Avenue, Baltimore City State's Attorney Ivan Bates announced on Wednesday, April 17. Thompson, who was 18 years old at the time, has been charged with first-degree murder, conspiracy, and other related offenses, officials said.
Thompson, now 24, was identified as a possible suspect by a tipster who came forward last year, authorities said. Thompson had been hanging out with friends on the night of the fatal shooting before leaving early from a friend's grandmother's home, the tipster said.
"As Thompson was leaving he observed a dark-colored vehicle with two occupants inside parked on the street. Thompson told the witness that he did not know who was in the vehicle," according to prosecutors.
"Thompson stated he became paranoid and told (two friends) not to come outside because he believed the occupants in the parked vehicle were there to either rob him or retaliate against him for all the robberies he was committing."
He then allegedly told the two friends to "get the guns."
Thompson returned to pick up his friends and pulled up to Mason's vehicle, when they opened fire after drawing his attention.
"As soon as (Mason) looked up, they shot up the car," court documents say. "Thompson told the witness he emptied his clip into the vehicle," then fled and dropped off his friends before heading home to his brother, to whom he boasted about the night's action.
"Thompson stated that (redacted) told him that he was tired of him wasting bullets as he hadn't killed anyone yet," they state. "Thompson told (redacted) 'I got one tonight dummy, watch the news."
The following day, they realized that Thompson had killed an off-duty police officer, at which point Thompson headed to Philadelphia to get rid of the vehicle involved in Mason's murder, trading it for an Impala, investigators said.
During the investigation, Thompson was also identified as the leader of a drug organization known as "The Slickest Ones" that operated on Elgin Avenue, according to the Maryland state's attorney's office.
"In late 2023, the witness was reinterviewed by (police) and (an FBI agent). The witness consistently retold the confession of Mason's murder as it was told to him by Thompson," charging documents state.
"A cold case is still very much fresh in the hearts and minds of the victim's family," Bates said. "My main job as State’s Attorney is holding offenders accountable, bringing closure for those impacted, and ensuring justice for Baltimore, the victims, and their loved ones,"
"For far too long, the details surrounding (Sgt.) Mason's tragic death have remained a painful mystery," Metropolitan Police Chief Pamela Smith said in a statement. "However, the Baltimore Police Department, the FBI, the ATF, and the Baltimore City State’s Attorney’s office never stopped following up on tips and tracking down leads,"
THE MURDER:
Officers were called to Elgin Avenue on Nov. 4, 2017, where they two people suffering from gunshot wounds inside a Nissan Versa that was parked, leaving a woman was struck in the leg, and Mason was found in the driver's seat unresponsive.
Both were rushed to an area hospital, where Mason later died approximately two hours after his body was found. His death was ruled as a homicide by the Office of the Chief Medical Examiner.
"While parked Mason (and the woman) talked, drank, and listened to music," investigators said. "A dark-colored car pulled up next to the, a passenger called out 'yo,' or 'hey ya'll' and then at least one person opened fire."
Sixteen shell casings from two different 9mm guns were recovered in the area outside the Elgin Townhomes, the court documents state.
William DelBagno, Special Agent in Charge of the FBI Baltimore Field Office, added that, "while nothing will bring (Sgt.) Mason back or end his family’s pain, we hope they can take some comfort in knowing that law enforcement will not stop pursuing justice and holding accountable anyone found responsible for taking the life of one of our own."
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