BROCKTON MASSACHUSETTS, a 35-year-old man is accused of fatally shooting a 40-year-old man in a public park last year after his girlfriend allegedly told him the victim had disrespected her and demanded that he “do something about it,” prosecutors said.
Michael Thompson was taken into custody last week and charged with one count of first-degree murder in the killing of Mike Jonas, according to authorities.
Thompson’s girlfriend, 25-year-old Dayana Slade, was also arrested in connection with Jonas’ death and is facing one count of accessory after the fact.
According to a news release from the Plymouth County District Attorney’s Office, authorities responded around 4:15 p.m. on September 23, 2025, to reports of multiple people being shot at Finnegan Park near the intersection of Crescent Street and Montello Street in Brockton, approximately 20 miles south of Boston.
When first responders arrived, they found two victims suffering from gunshot wounds. One victim, whose name has not been released, was transported to a local hospital with non-life-threatening injuries. Paramedics attempted to resuscitate the second victim, later identified as Jonas, but he was pronounced dead at the scene.
Prosecutors said Jonas sustained four gunshot wounds and was also stabbed multiple times during the attack.
The Massachusetts State Police Detective Unit assigned to the Plymouth County District Attorney’s Office led the investigation.
“Through preliminary investigation, law enforcement learned that an altercation occurred at Finnegan Park immediately prior to the shooting and were able to identify Thompson as the suspected shooter,” the district attorney’s office said. “The defendant was captured on surveillance footage leaving the area in a black Nissan Rogue while accompanied by two women, one of which was identified as Slade.”
Investigators later located and seized the vehicle as part of the homicide investigation, but Thompson and Slade were not immediately found. With assistance from the U.S. Marshals Service and local law enforcement, the pair were located and arrested in Lewiston, Maine, on Monday.
During arraignments Friday, prosecutors provided additional details about the case. Plymouth County Assistant District Attorney Jeremy Kusmin told the court that Thompson and Slade were at Finnegan Park when Slade told Thompson that Jonas had disrespected her and said she wanted him to “do something about it,” according to reporting by The Enterprise.
Prosecutors said Slade remained in the vehicle while Thompson allegedly returned to the park and confronted Jonas. A physical altercation involving at least four people reportedly followed, and witnesses later told investigators that gunshots rang out.
Kusmin said that when Thompson returned to the vehicle, he appeared distraught, was possibly crying, and was covered in blood. He allegedly got into the passenger seat and instructed Slade to drive away.
Authorities said the couple later left the vehicle at Slade’s mother’s home, where investigators recovered what was described as an “arsenal” of firearms and weapons. Prosecutors said Thompson and Slade then disposed of their cellphones and fled the state.
According to investigators, Jonas was the father of three children and did not know at the time of his death that one of his children was expecting their first child.
Thompson is being held without bond, while Slade’s bond was set at $250,000. Both defendants have pleaded not guilty and are scheduled to return to court for a probable cause hearing on February 26.
