JACKSONVILLE, Fla. — A 24-year-old Jacksonville man already jailed on a firearm charge has been arrested in connection with a January shooting that killed a 45-year-old man on 103rd Street, according to the Jacksonville Sheriff’s Office (JSO).
Dominque Alexander, 24, was charged Wednesday, October 21, 2026, with murder, four counts of attempted murder and possession of a firearm by a convicted felon in connection with the death of Porfirio Rosario, 45.
The shooting occurred January 28, 2026, on 103rd Street near Britton Lane in Jacksonville.
Victim Shot While Riding as Passenger in Vehicle
According to JSO, District 4 patrol officers responded to reports of a shooting on 103rd Street on January 28.
While officers were responding, Rosario arrived at a local hospital suffering from a gunshot wound.
Rosario died from his injury shortly after arriving at the hospital.
Investigators determined that Rosario had been riding as a passenger in a vehicle when he was shot on 103rd Street. The driver transported him to the hospital.
Homicide Investigation Identifies Suspect
JSO homicide detectives began interviewing witnesses and canvassing the area following the shooting.
Through their investigation, detectives identified Alexander as the suspect in Rosario’s death.
According to investigators, Alexander was driving another vehicle when he fired shots at the car carrying Rosario.
Suspect Already in Duval County Jail on Firearm Charge
In March 2026, Alexander was arrested on a charge of possession of a firearm by a convicted felon.
He remained in the Duval County jail awaiting trial on that charge while homicide detectives continued investigating Rosario’s death.
On October 21, detectives obtained an arrest warrant for Alexander in connection with the January shooting.
Alexander was subsequently arrested on the following charges:
- Murder
- Four counts of attempted murder
- Possession of a firearm by a convicted felon
The Jacksonville Sheriff’s Office expressed condolences to Rosario’s family following the arrest.
“No matter how many minutes, hours, days or months pass, we will seek justice,” JSO said in its announcement.