MONROE — Monroe Police and deputies from local sheriff’s departments last week helped Rock County authorities arrest one of several suspects in a Janesville shooting incident in which several were hit by gunfire and one man died.
“On August 10, 2026, at approximately 9:18 PM, the regional Tactical Response Team comprised of law enforcement from the City of Monroe, Green County Sheriff’s Office, and the Lafayette County Sheriff’s Office, executed a search warrant for a residence in the 2000 block of 7th Street,” said the statement
The suspect, Marshaun Jones, 21, was taken into custody without incident, police said. The Tactical Response Team was assisted in the execution of the search warrant by the Rock County Sheriff’s Office, Janesville Police Department; and Green County EMS.
As a result, Jones is charged with First-Degree Intentional Homicide, three counts of Party to a Crime - Attempted First-Degree Intentional Homicide; and two counts of Party to a Crime - First-Degree Reckless Endangering Safety.
He was one of five people arrested after the shooting incident in Janesville on August 9. The rest include: Mantezz Granger, 20, Charles Crenshaw III, 20, Demetrius Cooper, 19; and Tyshawn Howe, 19.
In their own statement on the shooting incident, Janesville police described a chaotic scene in their city involving the young men.
“On August 9, 2026, at approximately 12:31 a.m., the Rock County Communications Center received numerous 911 calls reporting a disturbance in the 100 block of South Academy Street in the City of Janesville,” said the Janesville police statement. “Callers reported numerous people yelling and a physical altercation occurring. Prior to officers arriving, the altercation escalated, and multiple shots were fired. Witnesses reported hearing approximately two to six gunshots and later reported seeing a gray sport utility vehicle leaving the area.”
Once on scene, officers located three people who had sustained gunshot wounds. One victim also suffered an injury to the face after reportedly being struck in the head by a firearm, police said.
“Despite lifesaving efforts, one of the three shooting victims died as a result of his injuries,” said the statement. “The decedent was identified as Jason Kaplan, age 25.”
Police began searching for the gray vehicle immediately following the shootings; and eventually located it and the suspects.
Granger was taken into custody and arrested on charges of Party to a Crime - First-Degree Intentional Homicide, three counts of Party to a Crime- Attempted First-Degree Intentional Homicide, and two counts Party to a Crime - Recklessly Endangering Safety. Mantezz was later transported to the Rock County Sheriff’s Office, where he will await his initial court appearance.
Demetrius was taken into custody and arrested on charges of Party to a Crime - First-Degree Intentional Homicide, three counts of Party to a Crime - Attempted First-Degree Intentional Homicide, and two counts of Party to a Crime - First-Degree Reckless Endangering Safety. Demetrius was later transported to the Rock County Sheriff’s Office, where he will await his initial court appearance.
It is unclear at this time why Jones was caught in Monroe, despite having a Janesville address; and whether the two remaining suspects had been taken into custody as of the newspaper’s deadline, Thursday.
Bond for Jones was set at $2 million in Rock County Circuit Court August 12, according to court records He is scheduled for an adjourned initial appearance at 3 p.m. August 26 in Rock County.
If convicted, Jones and his co-defendants face potentially many decades in state prison and tens of thousands in fines.